When he's overwhelmed, he pushes me out.

I've been dating my boyfriend for almost one year, and he was diagnosed with ADHD about four years ago. He's been on medication ever since, which seems to really help him focus at his job. His profession is extremely stressful; he's a therapist for adolescents from broken homes and many of them have committed serious crimes. The stuff he hears every day is super, super intense. It's been about one year since my BF got this job, and he's starting to crack under all of the pressure. In addition, he has financial troubles, had to move far away from me, family & friends for the job - and feels incredibly isolated. 

We have been getting into the same sort of argument for weeks now. I tell him what I need/looking for, and he seems to get overwhelmed by it. It seems that no matter what I ask for, he always says no. Basically we went from seeing each other several times a week to once or twice. I am the type of person who needs more attention, I guess, or quality time spent together. It seems like we aren't matching up right now. He feels overwhelmed by any more time spent than that, and it's slowing making me turn away from him. Honestly I think this series of fights has made him look at me in a different light: as if I am now a chore, or something else that he has to "take care of." I do feel bad for "putting him down" and making him feel like he's a bad boyfriend.

Admittedly, I have put him down quite a bit, and I wish I could take back those words because I know they didn't help. It was like kicking a puppy when he was already down :/ 

I don't really know how to rebuild our relationship at this point. I am willing to try and be more patient and give him the space he needs to sort through things. He is actively looking for a new job and hoping to move back home. I think much of this would be resolved by that, but in the meantime it's really hard to wait. 

He's never been able to sustain a relationship while in the every day. His mother told me that when he feels "overwhelmed" he always looks at the relationship as something that could possibly go. He told me the other day he doesn't want that to happen to us because I'm such a great person & and he could really see himself with me. He wants to actively try and have everything.

What do I do when he's overwhelmed and pushing me out? My only solution at this point is to delve into myself again: find things that make me happy & start going out and doing them. It's so sad to see what's happened to my BF in one year. He went from a charismatic man who had loads of hobbies and friends. Now, due to his overwhelming job & lifestyle, he has fallen into a serious depression where he no longer does any of the things he used to once do.

Any help would be appreciated.