ADHD boyfriend is so up and down!

I have posted in a forum before and got a lot of negative replays saying I should run and not out up with him, etc. So I'm a bit hesitant of posting this. 

the guy I am with has extremely bad ADHD. The saddest part is, that he has never been taught how to properly deal with it. He was on pills for it which were ones that also dealt with his anxiety and depression. He went off of his pills though and hasn't been as up and down since he stopped them. 

We met back in august, and instantly connected. He wanted to be around me all the time, started moving his stuff in to my place. Everything seemed like it was meant to be. But then, life got in the way. He was dealing with a custody battle with his ex, got a message from a girl that he had a fling with, stating that she was pregnant and it was his, and with that, everything started to go to hell. It came so fast, and left even faster. I could tell that he was trying to be happy with me, but started pulling away and I eventually found out that he was seeing a friend of his behind my back (she is younger and parties a lot. Not a stable person and not settled down at all). I told him to leave. I could see the confusion and the hurt in his eyes. I even saw him cry. But, he packed his things and that was that. My heart was shattered. 

After he left, he wouldn't leave me alone, like he was obsessed with me and had to talk to me. I blocked his number, but he would screen his number so he could still call but not text. After a week and a half of this, I told him I would go for a drive to talk. We started hanging out every evening, while he was technically still with this other girl. We were just friends though. I understand him a bit and he feels comfortable talking to me. 

He told me he made a big mistake and wanted me back. He pushed me away because he couldn't deal with everything that was going on, plus work on a serious, lifetime commitment to me, and give me everything I needed. I got it, I understood and I knew he was being honest with me. 

Hes back in my home now. And I love him. He gives me attention and affection. But, now we have another issue that is confusing him and causing problems. The girl he was seeing before he came back to me is pregnant, and this time, it's for real and for sure his. He knew there was a possibility of her being pregnant when he chose to come back to me. But because him and her do not get a long at all, and he doesn't see a future with her, he followed his heart. 

He won't fully commit to me, even though he is living with me. He says that he needs the freedom to deal with this other woman and the pregnancy without me being able to tell him what to do. His brain is all over the place now and it's hard to deal with. We were fighting about it and his mother got involved and told me to kick him out and freaked out at him. He called his ex (his daughters mother) and broke down and asked her to talk to me and tell me not to kick him out and help me understand what he needs from me. She told me to stop pressuring him and to just be supportive. She told me that pressuring him will just push him further in the other direction and if I just stop, he will make the right decisions. they were together for 6 years, and went through a similar situation when she was 6 months pregnant, so she kind of gets it. 

I just don't know how long I should give him to figure his shit out. The past few days, since I talked to his ex, things have been a bit better. I havnt pressed the issue with him and have just been letting things be for now. I'm trying not to be selfish, as I know that he may leave to be with her, since she is having his baby. I get it, he might figure it's the right thing to do. 

I guess I just need some support through this. I'm happy with him and he is happy with me, I just wish that life would give us a break for once. It just keeps throwing stuff at us, testing us, and it's hard to handle. His brain needs a break to figure his stuff out. 

How do I help him? Is there even anything I can do or should I just let it work itself out and not pressure him, like his ex said?