begood
I think you are bloody brilliant for wanting to help your sister in the first place. Not everyone would, lots would leave it for 'someone' else to do. I'm not surprised that the CBT or hypnotherapy didn't really work, as I suspect she wasn't ready to deal with all of the horrific things she's been through.
And if she was still using drugs and alcohol to block out and supress those memories, CBT etc would have been little use to her.
How awful for you all. You must be utterly exhausted with it all. And this isn't just about her is it? Someone who abuses drugs and alcohol to such an extent has a massive impact on the entire family, everyone around her.
All of you can see what's happening here and you want to help but the time has come (understanably) where you just can't take anymore.
There is lots of RL support out there for her, heaps of it, right at the end of her fingertips. 24 hours a day.
But SHE HAS TO WANT TO STOP ABUSING drugs and alcohol. This has to be her choice. SHE has to take control and make that first move to stop completely.
And it has to be completely. Cutting down the booze and drugs will not help her. No in the long run.
Maybe give her some of the websites listed above or see if she would be willing to go to AA or even her GP.
She needs help, real help but only SHE can get it and she has to be ready to take control.
One step at a time. Small, controlled steps. A plan of action if you like so that she can see where her life is going. So she can see the achievements.
I can't begin to imagine how hard this is for you and I'm sure your own life has been put on hold or suffered because of this. But FWIW - well done for seeking further help for her. 