I've been thinking about my role in it all lately too - things I could have handled differently and things like that....such as not being afraid of voicing my concerns and being a bit more encouraging when he mentioned going back to AA after a year away. It's tricky...on the one hand I feel yes I could have been different and I have pangs of guilt but on the other hand I was fighting his addiction with little knowledge at the time and doing what I thought best, especially towards the end of our relationship when I was very detached from a lot of his behaviours (him missing work with hangovers, him being sick, him forever saying he was stopping etc etc) and maybe came off as uncaring? At the time I was trying to protect myself I guess and him being an angry, abusive 'stranger' made it easier.
I have learnt an awful lot and maybe one day I will be able to apologise to him but I'm still licking my own wounds and working on fixing me.