I actually get what you're going through. I have divorced parents, and my dad only was into serious substance abuse and was emotionally and sexually abusive (hence: divorce). I tried to make it work and keep up some sort of relationship until I had a daughter, and then I just couldn't. Lots of therapy later, I know that was the right call. He'll never have access to my kids. And I just stopped getting in touch, no declaration or anything-- but I wasn't sure it was forever, and was working with a therapist-- and he's made no effort to get in touch with me. I send a Christmas gift, my stepmother sends our family Christmas gifts, and that's it. It's been 8 years, and I suppose I'll have to go bacK for his funeral. But not before.