You're not alone. Your story sounds a lot like mine. From my experience, I agree with LexieCat...that "high functioning" period invariably leads to a chaotic downward spiral if drinking continues. It's up to you whether to stay or go. I stayed, but I nearly lost myself in the process, and I don't know if I would have stayed much longer if AH hadn't reached out for help.
First things first - take care of YOU. Whether it's going to Al-Anon or reaching out to family & friends, build yourself a support network. It's so easy to feel alone, especially when you're geographically isolated from family, but you are very much not alone.