25M Need advice on what should I do next

I'd crush on a girl 25f, we're in same department in clg. I was too much of a chicken to confess that to her, I only spoke to her like 3 or 4 times, that too related to studies. But during my final sem and it was lockdown, I texted her saying that I've a crash on her. First she asked is it a prank? and then I detailed it a bit and then we started texting for sometime and after some months she said she doesn't want to talk (for no purticular reason).

I thought i might be disturbing her so I left her. But I couldn't move on so after a year I texted her again, But she seem to be in a bad mood so she asked what i want in a rude way with the f word, before I end the convo I shamelessly proposed her and said I try to move on. After some 3 or 4 months I got a text saying "Hi", she asked sorry and said we can be friends. I said I can't see you as a friend but we can try to understand each other and see how it goes. Additionally she said she got clinical depression and undergoing treatment so she won't feel any emotion something like that. Backstory is done, now I move to the problem.

So she texted proactively for some time (maybe like 3 or 4 weeks) and after that I need to start the convo i need to put all the efforts. At some point i got fed up and decided to end it as it took some toll on me mentally, i said we can be friends and I will stop pursuing her. She said ok and I didn't text her anything for some weeks, then all of a sudden she started texting me proactively. And stupid me, i thought she is acting like this because of her depression issue, so I thought of giving it a try and after some time same thing happened she won't text or won't even reply to my text same day, she will reply after 1 or 2 days, one time i even asked shamelessly about the late replies, for that she said she was busy.

This cycle has been going on for sometime. I've been stuck like this for quite some time, due to this I couldn't mentally engage with any other girls in my office or friends circle. I even got a proposal, but rejected it.

I feel like she is just breadcrumbing me for attention but on the other side I think she is acting this way because of her mental issue. Maybe I am not mature enough to handle this, need your advice people.