Realship problems

I was dating this guy for almost 2 years we were on and off and finally got it to work but it didn't last long tell the problemas came back I see less of him I feel like we're like strangers.. all he says that he can't explain and it's for the good of both of us I have been holding on for about 3 month and am tried of him not paying attention to me. Leaving me alone when I need him the most he less affection there only a few messages and he is gonna tell the next day is the same thing I left a message for him on my Facebook and dessactative my account and am trying to stay strong and leave him behind but I can't I really love him but I can't with the situation anymore how do I move on 😭 how do I not cave in😭😭