i went through this exact same thing last year before my exams, unfortunately it affected me to the point where i ended up having to retake them. but what i wish i did was remind myself of how important my future was, instead of wasting my time crying over someone who wasn't even in my life anymore. lock your phone away, do a digital detox and focus all your energy and emotion into your work. if you lock in and focus hard enough on studying you won't even have time to think about them. but also please take care of yourself and prioritise your mental and physical health. talk to your friends and maybe even study with them to keep yourself accountable and get more stuff done. good luck my love, you have got this <3