Closure--that was the thing that kept me hanging on to have contact with him... and it never occurred. I think i even remember him drunkenly telling me he wouldn't give me one, when I was finally just begging him for one. So, don't go looking for closure with him actively involved in your finding it.
I began seeing a therapist somewhere toward the end of us... or "the beginning of the end" of us... and she told me that I CAN find closure. It's going to come from myself--remembering who i am, what i deserve... it's going to come from positive people in my life--supporting and reinforcing my sense of self... and for a while, like it's doing for me right now... it's going to come from the bits of news we hear regarding the ex--because he'll cling onto the pattern of alcoholism destroying his life and everything around it, and this will again, reinforce our decision to leave.
When you start to thinking those thoughts of "i could have done this" etc etc... go with the thought and pretend you did do it--then further the thought to what his reaction would have been (because if we know one thing--it's that addicts have very predictable behaviors)--this should then reinforce that yeah, nothing would have changed... even if you had done something differently... reacted to a situation differently... etc.
i'm sorry for your pain. yours ended in march--mine ended in january... emotions are going to be a roller coaster for a WHILE... just remind ourselves that
