Hello again OP! Just to clarify, when I said you both had hard jobs I meant you are in charge of looking after your DCs.
I don't want to sound patronising but I would urge you to change perspective. The narrative you're telling yourself is very biased and guilt driven. Maybe talk to yourself the way you'd talk to a dear friend?
My dad blamed my mother for my sibling's genetic disorder (something completely different), and everything else would be her fault too , any trait of our personalities he did not enjoy would be something we had taken from 'that side of the family'. As a child that was hard to see. Such a cruel thing to do to her, and us too. It was hard to see my mom putting up with that, I know she was also feeling territbly guilty.
She should have not. It really does not make any sense to blame a partner for this. I'd be more worried about what the impact of his behaviour ( something he has got actually control over!) On your DCs is
Your DH needs to come to terms with the fact that perhaps his life hasn't turned out as easy as he hoped, stop being childish and blaming others ( I m being v. Kind to your husband here).
He has DC he should be loving unconditionally irrespective of their conditions...just the way they are. and he id supposed to love you just the way you are.
I hope you have a safe financial set up (your name on the house etc). I'd collect evidence of affairs and his abusive behaviour ( i am sorry but that's what it sounds like)
BTW, I don't have an ADHD diagnos but have many of the symptoms and understand the struggle with staying on top of things. It's hard. He should be understanding and supporting you, not telling you off.
Life is too precious to be treated like this.
You need to get out of the guilty trap and be kinder to yourself.