I am so sorry you are hurting.

If he broke up with you, as sad as it is, it’s wise to give him space and not try to change his mind. I’d especially be careful if he doesn’t respond as it could be just perceived wrong. Continue pursuing people when they don’t respond could be seen as harassment

I’ve been in situations few times in life when I ended relationships, but men continued pursuing me because THEY wanted to work it out. They didn’t respect my reasons for break up.

It might appear sudden to you but it might not be sudden for him. Regardless of the reason for break up, he made that choice. It’s probably better to grieve, process it and then move on. Good luck