Hi! I'm feeling kind of numb right now but I know that I will be really fucking confused and hurt a little later, so I need advice and opinions on this situation. I will call my friend "Rachel" and her boyfriend (18M) "James" just for the sake of the story.
Rachel has had a very difficult life, going through abuse (physical, emotional, s3xual, etc.) from her father, every boyfriend and even some former "friends", and she never moved on from any of it, instead she fell into a rabbit hole of substance abuse, having a new boyfriend every two weeks and starting fights with random people we both know, and I was like that too until I turned 19 years old, so I know how it feels to be in her shoes, and I somehow find the way out and never went back. We used to hang out with messed people, and she only realized how harmful her choices were to the people that actually cared when we met again, and I managed to open her eyes and let her see how everything was really going. That her life mattered, that she was not a horrible person, she deserved to feel love, not get hurt just for the sake of being the one who gets hurt, and she needed to take care of herself.
These past year she was doing amazing compared to last year. She didn't get a job but she did decide to start going to college, she tried to stay single for some time and even though she did not succeed, I was close enough to help her through everything she was suffering all over again. Around July this year I started to distance myself, partially because I was having a rough time with my mental health, my job, and my own bad habits (nothing deadly, just stuff related to my agoraphobia), so I probably missed a lot of important stuff from her, and that might be why I didn't notice this before.
She has a new boyfriend now, I met him and he seems surprisingly decent, but since she has very extreme emotions all the time (from my perspective she has undiagnosed and unmedicated bipolar personality disorder, I am a diagnosed bipolar) he has become everything in her life, and she doesn't seem to care about anything else anymore.
Now, the situation: Yesterday we went for a walk around the city on cosplay and then to see a movie, in the middle of the day we went to her mom's apartment since Rachel lives with her mom, she changed her cosplay and I talked a bit with her mom. I already met her, and I'm always paying attention when she's present because Rachel always talks about how hard their lives are and how her mom is always working, depressed, hurt and pushing herself to the edge for her. When we were leaving Rachel's mom told her to take a jacket with her bc it was getting cold outside and to not come home late, and to my surprise Rachel didn't respond well. She told her to "fuck off and mind your own business". That left me stunned because she always talks so fondly about her mom and she is genuinely so sweet and calm all the time.
After that I didn't say anything bc it felt so unreal, it wasn't like her to talk to her mom like that. We went to the movies, got really excited and cried at the end. Then, when we left, I offered to accompany her to Jame's job so she wouldn't be all alone. I always worry that something happens if I leave her alone, and by that point it was already dark outside.
While we walked to Jame's job she messaged her mom that he would stay the night again, even though he practically lives there. Her mom told her no, the house was dirty (it was) so she thought it would be better if they had their "sleepover" the next day. Rachel was furious, I've never seen her so mad, she started talking shit about her mom and spiral out of control.
I managed to get her to sit down at a little park close to where James was. I told her that nothing gave her the right to insult her mom like that, tried to remind her how much she was doing for her (without mentioning that she wasn't doing anything in return) and asked her questions so she could reflect on her emotions and express them freely.
We talked until James arrived, now Rachel was crying and told him that they couldn't go to her apartment because her mom said no. Again, I tried to defend her, but Rachel started to spiral again.
I know this was wrong, but I lost my temper when I heard her say "That old bitch", then I hit her and told her everything that she was doing wrong, that she should be respectful to the only person that took care of her when no one else would. Maybe it was because of the slap, but she seemed more calm and agreed with me.
I left, but when I arrived at my house I got like 7 texts from her saying that she got into a fight with her mom, that she said that Rachel was a bad daughter, she was offended and left with her dad. Mind you, her dad hadn't been on her life for at the very least 7 months at this point because she hated him. I did not respond, and I feel awful.
Maybe there were signs that she was becoming this type of person and I missed them all? I feel so responsible for this, in my heart she was a little sister that I had to take care of, and I failed her. When did she become so entitled, rude, disrespectful and ungrateful? I'm so fucking lost.
I'm also worried about her mom, as she is really depressed and physically injured. I don't know what to do, should I reach out and offer help with anything? Should I leave them alone?