First, big hug. You've been through so much. It's going to be ok. Not now, and not for a while, but it's going to be ok.
I feel so stuck in the middle I’m at my wits end.
I've felt this way too. There are things you can do to help yourself survive this season and we're here!
I do think think my GD is starting to make some bad choices. I think she is doing the rebelling she was afraid to do at the appropriate age. I feel like I should let her make her own decisions because it is her life and that’s how we learn, sometimes by mistakes.
If your GD is 19 it's likely that she is ready to take some steps to be independent. I think it's ideal that she's chosen to live with you. She's safe. No kid her age makes all the right decisions.
Priority one - where can you find more support? You're dealing with some heavy family dynamics. You've joined us here and that's wonderful. Are you open to finding a therapist? Is there a support group in your area? Who are the friends you talk to about this? Would you like some book recommendations? In my experience, the more support avenues you take advantage of, the more likely you'll be successful in this season.
Next step may be to untangle your relationship with your daughter so that you can see clearly enough to help your GD. It may start with setting boundaries with your daughter so that you have time to sort through some of your heavy feelings. How does that sound?
If you need something specific, don't hesitate to let us know how we can best help you. You're doing great, and you're going to get through this.
pj