Welcome Annie630:
I'm sorry about the situation with your mother. Another member had a similar situation with a BPD mom with cancer a couple of months ago. You have your hands full with your children and a traveling husband.
It's okay to say "no" to your mom staying with you after surgery. Perhaps she could go to a skilled nursing facility and after that, get help at her home. Don't let fear, obligation and guilt get in your way. You have to set boundaries for your benefit and the sake of your family.
The links below can be helpful: (Click on the green words)FOG BOUNDARIESAlthough Cancer counseling might have some benefit, I'm thinking your mom need some counseling and meds for her BPD.
Can you get some counseling for yourself? You need to take care of yourself. Can you think of some alternatives to drinking wine, for relaxing?