A simple response to your clearly complicated situation: you cannot control them. You can choose to go and the parameters you set (ie, a plan for leaving if you start to feel a certain (bad) way, how you behave/who you spend time with (ie focus on the kids), etc) and when you leave. If you decide to go, you have to take responsibility for YOU, only.
Personally, as the alcoholic and with an alcoholic mother, I am ruthless about where I go and what I do, and when. I seek peace in my life and there is very little that I would consider "having" to do if I could not decide to go in positivity and accept my role in being there, and how I handle the situation. Things that cause me great anxiety aren't on my to-do list. And I don't expect my mom/parents to include or do things with me that cause them "grief" of any kind.
Good luck.