My best friend's mom is messed up?

My best friend's mom used to be a cocaine addict and an alcoholic. She also has OCD and gets very angry easily. I always hang out with my friend and I am around her mom a lot. Just yesterday, My friend and I were out at my boyfriend's house late at night. Her mom called and demanded her home or else she would call the cops. I walked home with my friend while she was hysterically crying. Her mom was in her bedroom and my friend asked me to sleepover because she was afraid that her mom would hurt her, so I stayed over. My mom picked me up in the morning and just recently I got a text from my friend that her mom thinks im a skank and im not allowed in their house anymore. This is messed up I don't want to lose my best friend.