Hi, Megan,
First off, I'm a paralegal and work with the state's family court system. Unfortunately, I see these situations every day and I see some that are far worse. I've been doing this for 24 years and have heard every story you can imagine and a few that you can't. I'm asking you to remember one thing, there are two sides to every story. There may well be things going on here that you're not aware of. We parents certainly don't tell you kids a lot of things. Please give your Mom the benefit of the doubt here. I know it's hard on kids when your parents don't stay together, in a perfect world, this wouldn't happen, but ours isn't a perfect world. Even we grownups make dumb mistakes sometimes. Don't be mad at your Mom, it will only make things harder for all of you.