How do i deal w this situation?( Consider me as your lil sister and give me advice)

I’m really struggling right now. I went through a breakup just before some really important exams, and it’s been affecting me a lot mentally. My boyfriend cheated on me with my own best friend, and neither of them seem to feel guilty about it. Meanwhile, I still find myself wanting to text him and making excuses to reach out.

My 12th board exams are over, but I have major entrance exams in just two weeks that will decide which college I get into, and I can’t focus at all. While studying, I suddenly start crying thinking about him. I even tried reaching out, but he responded rudely and pushed me away. i do have friends but i dont open up that easily.. these 2 (my bf and bsf) were my only go to when something happened, since i trusted only them and now its eating my soul away.

If someone who has been through a heartbreak during exams, what was your mindset like, how did you push forward?

I need a elder sister-like advice and support on how to be mentally stable and a final push to do well in the exams.

Thanks, lots of love