Here is the tricky part - the part that I work on most these days since alcoholism is no longer in my life...
By not going you are doing exactly what your mother is doing. Behaving co-dependently.
My kids are older. I am not perfect. I grew up in a codependent/alcoholic brew and I interact with family that I described. It is all I know and unless I give it a lot of thought and attention it (that crazy codependent stuff) is how I cope, manage, get through life, parent etc. It is all I know. (or knew - I'm learning!) The mind ***** will impact my kids the same way it impacted me and that twisted way of dealing with life is something I do not want to pass down to my kids. Their legacy is already fraught with dysfunction. I divorced their father to change that legacy and I have to do my part too.
I don't mean to say this one night is going to be the end of the world. Don't take on more stress
I only want to encourage you to look at your 'giving in' as the next generation of codependency. From what I witness codependent woman give their lives away when their families are young - willingly at first and then grudgingly. As they get older they begin to get crazy with a capitol C about getting what they want and their needs met and they use what they know - which is mind *****, manipulation, and martydom. The thing is - what they need is not something their family can give them.
I'm not going to be that person. You and I have a gift that maybe they didn't have - lots of access to support and information like SR and counselors and al-anon. We can change that path for us and for our children.