I'm upset that my mom got back with her ex
Did something happen that caused them to forgive each other?
She was the one who asked him to start this relationship with her because she wasn't capable of anything anymore
It can be hard to see your parent making a mistake and being with somebody that is not right for her, but you shouldn't interfere. She is an adult and should make decisions for herself.
It's too late, I've tried talking with her but I feel like she doesn't care about me.
I think that you should try to be happy for your mom. It is not okay to be upset over the choices that she makes in her own relationships.