What is going on here? I need honest answers, I am so depressed!!!?

There is something going on with him. If he really didn't cheat on you then he is going through something where he isn't great. What is best for you two is to not be together. If several months from now you two are single then fine but you should concentrate on yourself. Get yourself busy with friends, hobbies, movies, etc. Way to get out of being depressed to stop letting yourself stay there. You need to tell yourself hey no more get busy and move on. Never wait around for a guy because you could miss out on a guy who is better for you. cheer up :)