This is a common problem among young people. He is full of conflicting emotions just as you are; he cares for you, but knows something in the relationship wasn't working for him, so at the same time he wants to try with someone else, but doesn't want to lose the chance to come back to you in case another relationship goes even worse.
He doesn't know how to process all of these mixed emotions, so he just communicates it as well as he can. Learning to express ourselves is an important ability, but it takes time and trial-and-error.
