Not sure if this will help - in my experience acting out is almost the opposite of being a perp. For me, when I act out (not usually involving sex) I am trying to find power and control "safely" (though often my actions are self-destructive.) That is by taking control over hurting myself or devaluing myself so that noone else will do it to me. But I never act out by taking power or control over anyone who is weaker or more vulnerable to me.
In a strange way, acting out is effective - it sort of maintains a working distance between my adult self and my child self. As though I am "abusing" him. But in doing this, I am keeping others out of the whole equation. Like noone else is going to get affected by my rage or fear - just me.
So, the fact that your partner acting out goes against everything he believes in makes perfect sense to me. It is as though he is protecting you, your family and his beliefs from the part of himself that he probably feels is "bad."
Again, this is something I've worked alot on trying to understand but take it with a grain of salt - I am sure as recovery goes on, I will have new insights of my own.
I would recommend reading what some professionals have written. Check the MS site for good suggestions.
Oh, and an important caveat, as for understanding not making it hurt less - I understand very clearly "what's going on" but unless I stay really mindful all the time, I still act out sometimes, though increasingly in less dramatic ways.