What works for me is knowing that there are many others dealing with this same issue right now, and many others who have been through it and survived. You are not in this alone!
My AH and I were on again-off again all summer, until I finally found the courage to set some boundaries and leave for good after an especially violent episode. Walking away from an 8-year relationship was frightening, but I have to remind myself that he wasn't ever truly committed to the marriage because his "lover" is the bottle. He is emotionally unavailable.
If your AH is irritable, angry, etc...those feelings are HIS responsibility (not yours). And yes, alcoholism stinks. For those of us who love the drinker, it's incredibly painful to watch them commit suicide by the installment plan.