How to deal with a breakup

I just broke up with my boyfriend of 2 1/2 years because we were doing long distance and I felt it was the most loving thing to do for each of us long story short. We still love each other as people but through social media I’m starting to see him do things like go on dating apps and stuff to cope. It just makes it too real and I feel gutted like he doesn’t love me as a person anymore and I don’t want to think that. I know I’ll always love him even if we aren’t in love and it’s heart wrenching.