Suggest me a book to get over first breakup

College student here. I actually dumped my ex a few months ago because I didn't see it working out long term but ever since I've felt guilty, regretted the decision, and have had just a really hard time in general.

I thought this feel was supposed to pass but it's been two months and I feel like I haven't really made any progress. It doesn't help that I have to see her everyday because we are teammates on a sports team. I also can't really talk to any adults in my life about it and my friends are definitely getting tired of hearing about it lol.

So if anyone has any book recommendations (I'd prefer fiction) for helping with this feeling and stage of life I've now found myself in it would be much appreciated. A little bit about my tastes, the last book I finished was The Poppy War by R.F Kuang. I like fantasy, but it was a little dark at times, and one of my favorite books of all time is Ender's Game. I also like history and am a stem student. Thanks!