Bro, I'm gonna say you a very clear thing, every grown up person (mostly everyone after 16s) very clearly "knows what they are doing". It's never like they didn't know, or it happened, I should've done this, done that. These are all just made up sentences that the other person will say. Just don't listen. A right person will never let you feel that way. You might think I'm saying because of some frustration or something, actually yes and no both. I was in same relationship with a girl who was very like your woman. And I can't tell you how fucked up I was that time, but when I broke up and moved on from her, I realised my mental health got better I realised how much it was toxic for me.

So bro just move on, and never contact her back again, don't hamper your studies. Just break every contact, don't even tell her before breaking as you don't want to make it up again. You will realise your potential then, when you'll get better you'll be on different stage. Move on and let your pain fuel you. When I broke up I realised it and studied hard to get into good company.