No Idea How To Deal With Partner

Hello, I'm new and I just want to say what a relief it feels like to have a safe place to talk.
I'm 23, my partner is 26 and we have a one year old daughter. He also has two sons (5 & 4) from a previous relationship.
He's been an addict as long as he can remember. He started smoking weed at 13, doing cocaine at 15, doing Mandy, Ket, any kind of pills etc since then and started seeing prostitutes from 17. I met him when he was 23. He had already been to rehab for cocaine (which had gotten really bad) and had broken free of addiction. He occasionally used it if going out but he no longer felt the need or desperation to use it. Since we've been together he occasionally went out with a work friend who also "gets on it" if going out. He would do drugs then but the addiction was kicked and he no longer craves it. The constant, every day addiction now is marijuana. It's always been his constant, it hasn't even felt like an addiction for him I think in the sense that he doesn't even think about getting it and spending the entire evening outside smoking. It's not a question for him, he just does it, it's part of his routine.
Yesterday we had a breakthrough in that I actually got a conversation with him for the first time in a while. He hasn't got any money and it's two weeks until pay day so he can't get any weed. He knows he has to go without for two weeks and that's that. Yesterday he said to me that he hates himself. He wants to be a "normal" person and come home to his family and let that be enough for him. He said he knows he's treating me like s***. He knows he ignores me and he spends the evening outside out of selfishness. He hates himself for spending the majority of the time he has his sons as per the custody agreement outside smoking weed. He hates himself for not putting the money he spends on that on something for his family. He hates himself for wanting it, he hates himself for needing it, but he also hates me for making him feel that way. He blames me because if I was completely okay with it then he wouldn't think twice. I'm not a substance person, never have been. I can go to a club and not drink and still have a great time. I've smoked weed before but I don't like it. I've never tried any other drug. I've smoked cigarettes when I was younger but didn't become addicted. I don't understand the need for a substance to avoid life. He says I just have my escapism in other things; crap tv programmes or reading a book. That's how I avoid life, he just does it smoking a plant. But mine don't alter my mindset. They're not destructive, and they're not unhealthy or an addiction.
I hold a lot of built up resentment. When I was pregnant he said his work put a portion of his earnings aside and if sales didn't cancel then he would keep that money and that's what we would use to buy all the baby stuff. I told him time and time again we couldn't rely on that so he needed to put other money aside. At the last minute we realised that money wasn't there and had been taken by the company for cancelled sales, we had to get a government grant and I had to spend all of my money on everything or get things on finance. Bearing in mind at that time I had lost my job was heavily pregnant and no one would hire me so I ended up on benefits. I found out later that he was spending 20 a day on weed at that point. 140 a week that he spent on this stupid drug instead of providing for our child. I cant believe he did that. It makes my blood boil now, I hate him for being so selfish.
Now it isn't as bad. He spends nearly 300 a month still on it, as well as most of his time outside the house. It hurts my feelings that he doesn't care if I might want to see him. It hurts my feelings that he would rather spend money on that than doing something nice for me or our child or his other children. I'm not blowing my own horn but I'm a good partner to him. I understand he struggles with it and I don't nag him because I don't want to make his "relationship" with weed even stronger. I do everything, from 6am till 7pm I raise our child and care for her and put myself second and when he gets home at 7pm I'm downstairs cleaning the house for him to come back to a stress free home and then I cook dinner for him then we eat then it's already 8.30pm, on the average evening he spends probably 20 minutes actually "socialising" with me. I say this in inverted commas because actually I spend 20 minutes sitting next to a glassy eyed empty self absorbed man laughing at internet videos of an Australian goat doing something weird. I don't care about the goat. I want to spend time with the person I started a family with. I feel very stupid because for some reason I thought it was just a given that when we had a baby he wouldn't smoke it every day. I don't mind every now and then, like I wouldn't mind a glass of wine every now and then. He jokingly said to me yesterday that weed is the perfect partner, it doesn't answer back, it makes him feel relaxed and indifferent, it's always there for him and always has been throughout the trials and tribulations of his life. I wanted to scream at him SO AM I. I have always, always been there for him. Especially through addiction. I have tried to support him as best as I know how. We've come up with compromises before. Don't smoke it during the week but on the weekends smoke it only in the evenings once all the kids are in bed, and one of those evenings when e doesn't have his sons over I want an evening for me, I want him to spend time with me and on us. Apparently I was asking for too much. He manipulates and wheels his way in to make me seem like I'm unreasonable. I know exactly what he's doing when he does this, and I tell him so. Sometimes he's so convincing I end up arguing with myself. "He does spend less than he used to. He doesn't do it before work. He's a functioning addict he still works 40 hours a week and helps with cleaning and sees his kids. He does work hard. He did give up cocaine this is the last thing he has left. He is a caring dad. It could be a lot worse." It makes sense sometimes. And then I wake up and think NO! I've let him get in my head. He's using any excuse for it to be okay. Just because he isn't mugging people to get the money for it and going to prison etc, doesn't mean it's okay! He has an addiction to it so it's damaging and destructive to his family. I don't want my child and his kids to grow up with that as the norm. When I look back it sickens me as I remember him pushing his son's buggy down the road while smoking a joint. I can't stand that thought.
Now he's going to be in a rage while he tries to kick the addiction. I have no hope this time, every so often he does this and thinks "no enough is enough I need to stop being selfish" and then it goes back to square one. Before I've always been so excited to help and eager to support and this time I'm struggling as I feel I have nothing left. I already feel like he's lying to me as I know in two weeks when he gets paid it's going to go back to normal. I hate that that's my normal. I hate that he's brought this into my life. I hate myself for allowing him into my life when he has this problem. I hate that my daughter has a father who thinks that this is normal.

But, I love him. And I want to be with him but I deserve the best of him because I'm a good person, a great mother a great partner and I deserve so much more than what I'm getting and I don't undervalue myself. And I think that makes it harder for him because he knows all this and it makes him feel bad so he smokes a joint to forget that he feels bad.

What do I do? How do I help him? How can I help him help himself? He's in a more loving relationship with a plant than he is with me.
I want to say kudos to you for putting all of these thoughts together; I'm sorry it has been so hard on you and on your family. I completely understand the rationalization you are making and have had many similar thoughts lately (I was not married to the addict but I love him to this moment and it breaks my heart what he puts himself and those around him through because of his addiction). I keep telling myself that maybe I was too hasty to leave him and to get upset that he ignored me and yelled at me and was not the supportive, loving person that I want and need. There are moments where I hate myself for giving up on him, and I feel guilty and alone and sad.

The part of my brain though that reads these posts and attends Al-Anon meetings and learns about addiction knows that I made the right decision. He can't love me the way I want to be loved. I don't deserve to be tortured by him, and I don't deserve to torture myself for the feeling of having abandoned him. It takes 2 people to be in a relationship and no matter how much I loved him or did for him, I will never be at the top of his priorities.

If you are not already attending Nar-Anon or Al-Anon I would suggest you go to a few meetings, or at least read about their program online. I find it very comforting to know there are a lot of people out there like us who love someone who doesn't always have the ability to love themselves.

I don't know what your family background is, but I never had a good situation growing up and I think that's what drew me to an addict; I felt like I could love him and care for him despite his problems and that in return he would need me so much that he would never leave me. I've come to realize that I myself have a problem and that I need to focus on taking care of ME. You have these children who I am sure you are a rock for; I feel like for them and for yourself you should get some support and help to deal with this. I know the awful feeling of disappointment waiting for him to call or talk to me or spend even a moment of time paying attention to me. As much as it hurts, I am honestly less alone on my own than I was when I was with him, because I have no expectation of him acknowledging me (he hasn't spoken to me since I left him).

I don't know if any of this will be helpful to you, just my two cents (two pence?) - I hope you find some comfort in this site in knowing you are not alone in your struggle. I will be thinking of you and hoping it gets better.
Thank you so much for your response. It's comforting to know you're not the only one who is dealing or has dealt with this. It feels very isolating because I can't talk to family or friends about this, I don't want them to know because I'm embarrassed about it. At face value I would say my family background is nice and normal, my parents split when I was 11 and after a few years salvaged a courteous united relationship for our sake. They're both in relationships with other people now. I always looked after my mum who had a car crash love life, and at 15 I found solace in a (much) older man who after years of guilt I realised was actually grooming me, and it turns out he was just a paedophile (police found lots of other evidence and potential victims). I thought I was so in control of my feelings and myself at that time and to find out actually I wasn't, was pretty heavy. I think I was drawn to my partner probably because he was already a bit of a mess. He was a party animal who slept around and at first things were so casual, but very quickly we fell in love and he didn't want to be the persona he had adopted anymore. But, in the back of my mind I think I have always had a figurative expiration date. Our pregnancy was accidental through birth control failure. But we've made a terrific go of it and have done really well. In the back of my mind though I think I know our differences are so great that one day he will end up disappointing me so much that things end. I really, really hope that isn't the case but a part of my heart is numbed and used to that probability. I never trust anyone completely and although I'm certain he loves me and is in love with me, I assume that one day he will slip up and something will happen that's the end of us. In the three years we've been together he's never once shown me a real true example of his love for me or respect for me. He thinks he has done because he's never cheated on me, which he did on his previous partner through two children and five years. I suppose I'm hoping his love for me will be enough to change him as it has changed some of his behaviours already (not by me pushing him, he decided to change himself because he respected me I suppose). I know it's ridiculously foolish and how often do men actually change themselves for someone. I just think with something like this, why wouldn't you want to? Aspects of your personality can't be changed and that's just it, he sees smoking weed as a part of his personality. He says he is scared of quitting because that's all he has. He doesn't go to the pub, he doesn't really have any friends as they were all users (cocaine) and he stays away from that now. He doesn't like tv or reading or anything really. I think he's just been smoking weed for so long and from such a young age that he has no idea what he likes. He always filled his time and thoughts with substances so he doesn't know what he wants to do or what he might like to try.
Sorry I'm rambling but it's quite self soothing to put thoughts down even if no one reads them.