Like the other posters say - its ok that we lose our cool once in a while. We are human after all. It happens.
For me, it happened too often; I knew I had to leave in order to salvage my own sanity. For me, successful detachment meant removing myself from the situation causing such stress. I decided living with an alcoholic wasn't worth it, nor was trying to "detach" from behavior I already knew I couldn't and didn't want to live with.
You have that choice too, ya know. If he isn't trying, working a program, and violating your boundaries time and time again, why bother?