Thank you all for your advice! I’ve read every single post and the support has really touched me!

I have spoken to her before and told her there may be times where I need to back away for my own mental health. She knows she is a negative person and has told me she’s surprised I’ve stuck around so long, as no one else has she also said though she thinks she’s too ill to get any help. She needs a huge amount of help to be anywhere near well and so won’t even try

I think my plan for now is to back away slowly and just spend less of my time on her. I’ll reply to messages but will just be less available than usual and spend the time doing other things and with people who are a bit more positive. I feel sad but today just really got on top of me and it triggered my anxiety pretty badly. right now I need to calm down a bit before I reply to her messages so will leave it until tomorrow and give myself some time to think.