Have you tried therapy and support for yourself and your daughter? Al anon? At the very least buy some Al anon literature and read on your own. N-anon? Al ateen for your daughter if she is minor

No he won’t change. Unless of course he seeks treatment but even then he’ll always be an addict. You didn’t cause it though and you can’t cure it

As about trying to talk to him about this or that. There is this passage in one of the Al anon books (don’t recall which ones, I’ve read them when I was in a relationship with alcoholic and needed more info on it deciding to leave) it asks you if you’d go to pastry shop to ask for produce? No. Will you go to auto parts shop and ask for bread? No. They don’t have it and never will have it so no point in asking. Then why do you go to actively using addict asking for things they don’t have and cannot provide? He cannot provide you with treatmet or relationship or insight that you want. He is a produce shop and you are asking for dairy products.

Can’t answer why you are “like this”. There might be many factors at play. Was there substance abuse in your family of origin? Other dysfunctions? Again get into therapy for yourself. Not to fix him. Work on yourself

Get help for yourself and your daughter. You can’t change other people.