That sounds like a relationship we had with a friend. We wanted him to care so bad, and he never did. It was a symptom of our Borderline Personality Disorder; we were so attached to him unhealthily that we couldn’t let go and see that he wasn’t worth our time. There are people worth your time out there. Don’t cut her off, but look for more people. She isn’t right for the friendship level you’re looking for. There are people out there who are.
It sounds like your depression has really taken a hold on you. Try to fight it. It’s so hard, but try. Quite literally roll out of bed and plop down onto the floor. Crawl to the kitchen to grab a premade snack if you need to. Grab a wet towel and some soap and wipe your face and your body. Do the easiest version of everything. You’re trying to jump to the same height as everyone else, but you’re starting 10 feet lower than other people. Focus on jumping the same distance as other people. Jump 2 feet, just like everyone else is. You won’t reach the height they reach, but that’s not the point. You put the same amount of effort in, and that’s what matters. Their shower looks like your wet towel. Their freshly cooked meal looks like your uncrustable. Try the minimum output. You’ll be happier knowing that you accomplished something more than yesterday. Those self care things are super important for mental health. Maslow’s hierarchy of needs. You’ve got to eat and move around a bit before you can tend to other needs. Try stretching on the floor. Nothing specific. Just move your body and do stuff that feels okay. Little steps will still move you forwards. Wishing you so much luck.