I lnow O aleays try to defend myself.

That is really hard because we want to defend ourselves and convince them it’s not true. When I get caught up in doing that we both wind up yelling, adding to the stress. When I can stay calm and say something that seems to be agreeing with him like “Yes, I guess I’m a terrrible person”, it’s over quickly and he’s forgotten. I have to remind myself that he’s frustrated and I’m the safest one to lash out at. As far as him accusing you of seeing someone else, I’ve never had that happen. Maybe you could tell him that you’re sorry that he’s not able to believe you when you tell him that there is no one else. Leave it at that, let him rant, rave but don’t respond.