relationship advice?

I need advice. A couple of months ago I asked my boyfriend of three years if we could take a break. We weren't allowed to date other people on this break, we simply needed some time apart because we had been fighting a lot. He was completely against taking a break when I asked him about it. But then he agreed and three days into the break, he decided to break up. It's been really hard for both of us. He went on a few dates after we broke up but nothing serious. He said he didn't know if he was in love with me and needed to see if he felt the same connection with other girls as he does with me. We still had sex multiple times after the break up and we still talk every day. He says he knows now that he is in love with me. But he doesn't want to get back together because he needs to figure out what he wants to do with his life/career. We're only 19. I know, some of you will say that we're too young to be in love and know what we want. We're not. He said he's still in love with me and wants to marry me someday, but doesn't want to get back together right now. He's not dating anymore but he's been really flirty with another girl lately but he said he doesn't have feelings for her. I asked him why being with me gets in the way of him deciding what to do with his life and he always just says it's hard to explain how he feels right now. I feel like if he knows that he wants to be with me, then right now he's just wasting our time we could be spending together. Every time I bring up the subject he doesn't want to talk about it. I don't know what to do anymore. People have told me to just cut him off, stop talking to him completely. I don't want to do that because I feel like it would push him away from me even more and he would start paying more attention to other girls. Help?