Maybe you can focus on you, maybe start a hobby?

I can sort of indirectly relate, my ex stepmom married the person I though she was cheating with two months after her and my dads divorce was final, and I found myself needing to be surrounded by people that were actually there for me, not who I wished was there for me. Taking time to identify your meaningful relationships and investing in them will over time help heal those wounds, because I know they hurt

I dated my ex for almost 3 years. Things started going not so well so we broke up and he started dating one of my friends and coworkers a couple weeks later.. it's been 2 years now and I still think about him everyday and it still hurts. One of my biggest issues with the situation is comparing myself to her. The best thing I did for myself is take the time to learn to be alone and focus on myself. Do something you've always wanted to do, start planning something big and beautiful for yourself. I had always wanted to go to Alaska and I found a seasonal job out there for the summer. I met a lot of great people and learned a lot about myself. Travel really helps find a new perspective and get to know yourself better. hope this helps