So my SIL has been my BFF since before (only by about a month) my husband and I started dating (4.5 years ago). Bit of background - both her and I have very similar mental health issues and struggled most of our lives with them but I have chosen to do intrnsive therapy to help me and I have come along way, where she has only seen a psych on and off for the last few years and abuses her medication for fun, recently started doing party drugs again etc. Now I am not judging at all I'm just trying to give you an idea of how she can be. Recently she has started to get some pretty bad anger here and there and I have tried to help her when she has asked as it's something I've had to learn to handle myself - however I have never put my hands on anyone, where she has before her brother, partner, mum, attempted with me once but I stopped the situation. The other day she called me losing her mind and when I got there she jumped at her partner and grabbed him around the throat choking him, then she smashed out a flyscreen on her window and threw her phone into the road. But she couldn't tell me what caused this. A neighbor called the police then she went to yell at the neighbors for "bring nosey" until I stopped her. Things have been progressing in more violent out bursts over the last month to the point where she will fly off the handle at her partner or her brother (my husband) infront of anyone. I have tried to be understanding of how she is feeling and what is happening but over the weekend when I saw her do that to her partner (who is a lovely guy! ) I just lost a lot of respect for her. I don't think I can be friends with someone who does that to her partner and feels no need to apologise because she is a girl and she has mental health issues - it is domestic violence and it's not okay!! I've tried to distance myself from her a bit because I just don't know how I feel. When do you stop making excuses when someone is spiraling out of control but anytime we try and support her or get her support 'we don't love her cause this is they way she is because of her mental illness' - which I know is a load of shit because I have worked so hard to overcome my issues with anger and emotional instability. I guess I'm just at a loss - what would you do? Or wouldn't you do? Would you approach it? Leave it alone?