Reddit mentions of Healing the Child Within: Discovery and Recovery for Adult Children of Dysfunctional Families (Recovery Classics Edition)

Total respect for you to let go and forgive the things your mom, and sister have done to you. After all that you still love them. Not kidding, you are a real superman. Yeah, life is unfair. People don't love us all the time, and we have to respect that and move on. We have needs too. We can't wait for them to change. It's hard for me to imagine you and your sister going through so much so early in life.

I guess your sister needs to move on, and tell mom that she's there if she needs her anytime, and that she still loves her. Don't wait for your mom to change. Just move on. That doesn't mean you don't love her. You and your sister need to find a job(maybe part-time) to support yourselves since your mom isn't committed to support you.

On a final note, because of this traumatic experience, I would suggest making friends who are emotionally healthy. It's easier to make friends or fall in love with an abusive person. Be aware of that. Read books like Healing the child within to understand unhealthy patterns about yourselves. I'm not saying you are a bad person. Because of the traumatic experience, you and your sister need to find the right way to heal yourselves of the deep emotional injury.