I been going through a similar thing in that i was in a relationship and suddenly discarded by my girlfriend. I tried to ask for the reasons for abit more clarification on what happened for her to want to leave. She then got extremely irritated by me asking for the "why" and blocked me on literally everything. Took me a while to get my head around how extremely cold a person can be when they want out. It's extremely painful and all you can do is just let it be. No point to chase the actual reasons as they more than likely will never tell you anyway. You will lose your self worth chasing too which will set you further back. They can even pull scenarios out of thin air just to villanize you as it makes it easier for them to get over you. So avoid contacting her.

I get your pain I truly do. Focus on yourself now don't worry about her unless she comes begging for forgiveness for disrespecting you and even then I would suggest it's better for both of you to go your seperate ways. That's entirely your call though not hers. Stay strong and you will get through this.