I don't know what to do?

If you are dealing with addictions, get used to this. I'm surprised you feel bad, because I didn't feel bad when I was in your shoes. You need professional help first and then, once you're established with a support system, you can let her know. That way, you have a chance of keeping her. Show her that you're serious about getting better. But if you do get help, do it for yourself first.