Most Helpful Guy
Time to move on. He did and look at what it is doing to you. Now that you know, see what it does to him. If it was meant it will be, if not at least you moved on.
At 18 or so, sorry but the word "love" is thrown around too much. Not enough people mean it when they say it and say it so that they have something to say. Marriage. Should you not think about that after you get out of school and start a career. See and experience life and the world around you. Men (as well as woman) tell you that they love you but if they do not know what love is how can they say that they love you?
It sounds as if he is driving you crazy. Maybe he wasn't ready to MARRY as you/he thought. His actions sure sound like someone enjoying life, single or otherwise.
Carry on, date anyone/everyone. Date a guy, a girl, a three way date (date does not mean sex) have fun live life. Hop a plane, ferry, puddle jumper, train, bus - whatever and go to a town/city center near you but far enough away that you won't bump into him or friends. Enjoy the fresh start, even if it is for only the night. Be a tourist in your own backyard. LIVE LIFE!