Am I Wrong For This?

I broke up with my ex about a year ago because my friends told me he was cheating on me and when i broke up with him without even askin him about it. and the next day i went to school and my friends told me they we're only playing and it was a joke. I apologized to my ex for it, and we been "talking" for about a year now [[we started back talking on a relationship level around the time we broke up]] and it's been the same since then and now everytime i ask him when we're going to get back together he always says "i don't need to be in a relationship right now" or "we'll see" it's always something like that..is he only saying this because of what happened a year ago? everything else is fine in between us..we act like we're in a relationship but we're not..is it because of what i did?