I am also in the process of closing all contact with my ex addict boyfriend. And considering his erratic and aggresive behaviour sometimes, I am better doing that.
I don't think I can't stand anymore late messages telling me how he is going around all the women in his town (including pics), and the other messages a couple hours later telling me he was so high and drunk he can't remember and that his life sucks.
I think it can't be any downside to that and at the end it gives you a peace of mind that you need and want to bring happiness back.