Hi Jenn,
I just want to say welcome. You sound like such a smart lady, and a real peace-maker. But you also sound like you know that you are tired of having your mother's drug addiction affect all the special moments that you value in life. That is wonderful and you are so right to recognize that. Read up here, and I second GiveLove's advice on posting in the other forums as well. There is one for loved ones of alcoholics and one for addicts. Or just look over there at the stickies at the top to start. I hope you get a lot of knowledge here that you find supportive. It's so great to find a place where you gain strength from knowing you are doing the right thing by detaching. Good job!