They can still enable her because she is their child. And unless you have any children you just cannot understand how hard it is for a parent to accept addiction and accept that there is nothing they can do to help their own child.
It's not you personally. Their involvement is with her, not you.
I know it's hard, and you can question away, but your logical mind is never ever (hopefully anyways, don't become an addict) going to be able to follow her addicted mind, and how her own issues work in her mind. She is #1 for herself and you just don't work in the same way.
In all, it's been a very short duration. I know it may seem like a long time, but in reality, it's been a short time to allow yourself to grieve. And to stay in contact with her AND/OR her family only makes things worse for you, I promise.
I say this all gently because I know you are hurting.