I'm exhausted and don't know how to help 12M son.

I'm not sure what I'm looking for here. I guess I just needed somewhere to express my frustrations.

My son, 12, has ADHD. I have ADHD. Both of us also suffer from depression and anxiety, as I've gotten older (37) my symptoms are worsening. I love my son with my whole heart but I am exhausted. He is a good kid but with me he is defiant all the time. I feel like I have lost control and he doesn't respect me as his parent. Anything I ask him to do, there's push back. I can't rely on him to do anything even when he says he is going to and if he does... chances are it will be a halfassed job, i.e.. I ask him to pick up the trash on the floor in the hall and he will do some of it but leave obvious trash still there and I have to point every piece out.

Ive set up so many systems and he has no interest in using the tools I provide him. If I dole out a consequence there is of course a huge melt down but it rarely ends with him doing "the thing" without us both losing our cool. I've tried so hard not to, I really do, I know it doesn't help but as it said I'm exhausted. I'm a single parent, his dad is not in the picture (unless you count occasionally playing video games with him online or an occasional gift). No one else in the family has the patience to deal with his out bursts calmly.

It's the same cycle, I ask him to do something, he either says no or he'll do it in a minute, I repeat the request, I enact a consequence and he loses his shit. He tells me I'm gaslighting/bullying him/being mean. I try to disengage but he will not physically get away from me and continue to pester me until I lose it. I ask him to leave me (and usually my room) alone and he refuses. What do I do with that?! He's over 150# I cannot easily physically remove him without it turning into a power struggle, I still win but it's not gonna be long before he can probably match me. This is about where I lose it. Then he shuts down because I'm angry. Then he gets sad and starts hitting himself and talking about how he is a failure. Once I'm calmer I go try and settle him back down. By this point I'm heartbroken and feel like I'm failing him. Then afterwards he's usually ok, and I am not but I still have to continue on with life because there's no one else to do the things. It just feels like a cycle and I can't break it.

And before it's asked:
-We are both medicated though my results are eh at best.

-He's in counseling, though he refuses to talk about some of the big things he needs to deal with

-We are working with a psychiatrist to figure out meds

Like I said I just needed to get this all out before I go home. I'm just hoping he did the dishwasher and we can move from there and I don't have to repeat the cycle today, I don't have it in me.