Re: should I just confront her?
People are naive if they think friends will always be there and will always have your best interests in mind. Friends are there for social reasons to enjoy their company, have someone to talk to and share experiences with, can occasionally depend on them, etc. But they will not always be there and they will not always have your best interests in mind.
Those friends that stick with you through thick and thin and will have your best interest in mind are very rare. If you have a friend like that then you’re very fortunate and shouldnt take it for granted. But majority of friends are NOT like that.
OP unfortunately seems like you have issues with your family and had no one else to turn to so you trusted this girl with your personal issues. Your mom made mistakes in this also but I will still give her the benefit of the doubt, she likely wanted to be kept within the loop and was using her to get info about you without reaching out to you directly because of whatever you did for them to disown you, she clearly still cares about you to want to know about you but very bad way to do it though. But your friend likely did it with bad intentions to enjoy the drama and keep her distracted from her own issues–remember, misery loves company. Learn your lesson, keep personal things to yourself and don’t always discuss so freely with others even if they’re your friend. She clearly made things worse between your mom and you, she knew what she was doing. The best thing you can do is just move on and cut this lady out of your life. Doesnt look like she has that great of a life either–she isnt happy and has a lot of issues. No need for revenge or playing any useless games. Karma will take care of itself, if it hasn’t already.