Rosie I am so sorry for your heartbreak. As everyone here will tell you, you have to take care of yourself.
I think detaching is a good thing and I have the best I know how to....BUT for me, I know until my son is really living a clean life and happy, I will NEVER truly be completely okay. It will continue to haunt me and I just hate that. Even if he doesn't live the life I want him to live (traditional married with kids, normal job etc.) I will still be okay with that as long as he can look at himself in the mirror and like who he is. As long as he isn't a slave to addiction or anything else for that matter.
We he finds inner peace I know I will truly be free.
We're her for you.