try to understand this is tough on your son as well......he is an ACOA, he grew up in a household ruled by alcoholism - this meant from early on his "survival" was threatened and he had to make bargains with himself at a VERY young age in order to gain a sense of security. children will often bond to the more dysfunctional parent, in the hopes they will become the hero they wish them to be - AND NOT LEAVE. so in his warped sense of reality, you became the "problem" - if mom would just be NICE to dad, then dad would be ok - AND I WOULD BE OK.
remember he made that negotiation at a very young age......and it stuck and was reinforced over the years. it's not his fault. he's a product of his environment.