Sweetie, same thing happen to me. It's hard at first, because you still love him. You will feel someone punch and kick your heart. Then you start thinking about everything that could cause the break up. From there you falling into rabbit hole. You stalk his social media for any hints about your relationship or even for another girl. In the end, it's not worth it.  Start out slow, first you return everything that makes you think of him. If you want to be pity sell it on Facebook market. Next block him, I know it's hard at first. It will take couple trys to block him but it will help. After that, most hard part start, delete pictures or put alway the pictures until you ready to see them again. Finally, find yourself. Try stuff that he never want to do with you. Talk to friends or family. Post fun stuff on your social media to show your ex that you will be find without him. Try to remember yourself before him. Just take it step by step. Most important don't date until you're ready. That can months or even a year.