Loosing the spark

What do you do when you think you’re falling out of love or loosing the spark? Out two year anniversary is coming up and I don’t know if it’s because I’m starting college and working a lot or I’m just not in it anymore. I love him more than anything and have no means of breaking up but it’s not like he was before. I never want to have sex anymore and that’s been happening a while and I don’t really want to make out like we used to either. I don’t know what’s happening to me. Helllp.