loosing feelings?

so i dont really know who to talk to about this topic but i really need some advice... i have been with my bf for 1 year and a few months and although we had and still have our ups and downs, the last months have been amazing. But lately it just seems like something has changed but i cant put my finger on what has changed so its difficult to talk about it; we just dont seem to vibe like we used to. Actually what confuses me the most are my feelings towards him, they seem to slowly fade but on the other hand it breaks my heart to let him go...

has anyone of you ever been there?