Do I Stay or Do I Leave?

I am 17 and have been trying to pin a boy down since the 10th grade. This boy and I have been on and off for 2 years. We have never been official but we both have had feelings the entire time and hook up occasionally. He does not want to date in high school because he does not believe in relationships in high school but he claims to love me a lot and guarantees that if we both have feelings after high school, we will be together. BUT he also understands that it's not fair for me to wait for him, so he encourages me to move on. What do I do? Do I wait for him or do I move on?