Mom is losing her mind

(I wasn't sure if this belonged in relationships or disability so sorry in advance.) Before, my mom had her annoying qualities but she worked and had friends etc. My dad's bipolar disorder kicked in and they divorced (21/22 years ago) and she stayed strong supporting me, then my bipolar symptoms kicked in. My mom did her best to take care of me but it wasn't easy and I think it broke her. Her common sense evaporated, all she talks about is the past, and she isn't able to process information that is unfavorable to her. We did a lot of moving, and when I turned 19 I moved in with my boyfriend (he's a paranoid schizophrenic and much older than me). After that she stayed with different friends but they all kicked her out, she even stayed with some of my friends and that ruined my relationships with them. I convinced my boyfriend to let her move in with us and it has been awful. Today I played mediator again because she didn't realize when I told her not to touch his stuff it included the meat he sectioned off for his lunch tomorrow. Also I got home and she was outside in the cold coughing and shivering because she "didn't think to put a sweatshirt on" (she's anemic and has been since childhood). I have no idea what to do. She's too young to be considered a senior citizen, and I feel guilty that it's probably my fault she snapped. I have given up my life for her, including moving halfway across the country just so her family would help (they wouldn't help her with housing unless I was with her). I have no idea what to do and any suggestions are welcome, just please help me.