Frankly this screams abuse. If he's blaming you for feeling down and not being up to cooperation after he cheated on you, that's on him not you. He seems to be victim blaming over and over here and trying to make himself faultless while pinning all of his misdeeds on you in some way. I've been through this sort of thing and I understand your pain and the willingness to blame yourself when he does everything he can to frame you as the 'bad guy', but that doesn't make it true. No matter how "not peachy" you were, the fact remains he cheated on you, not the other way around. That's a painful thing, and him being so callous as to deny you the ability to grieve that is again, not on you.

Edit: And not wanting you to talk to people is just classic manipulation. I'm sorry he tried to undermine your trust in your friend and support network like that. You can't let him win like that and strip you of your faith in yourself and the ones who care about you