Tracy.
OronD is usually right on the money and I agree with every one of his answers. It happened to me as well. The last words I heard were, "I love you", he left and I never heard from him again. Of course we DESERVE an explanation but like ~nmbp~ said, we don't always get one. My advice, If a man if that "fickle" to put it nicely, to just "fall off the face of the earth" and never contact you again, you are better off for it. Better now than if you married the jerk (providing he truly is one) and he just ...walked way from the relationship and you are still legally bound to the guy. Just thank your lucky stars you found out in time. My "magician" who pulled a disappearing act, lived in another state so it was harder to track him down for an explanation. Don't give him an "easy out". If he lives near, go there. You deserve an explanation, demand you get one and if you don't get one, just have the self-respect just to smile, say nothing, turn around and walk away with your head held high. My guess? He may wonder why you are smiling!!!!
Good luck, hon. Those types are the hardest to get over sometimes because you just never will know why. Move on and remember, his loss, NOT yours! Good luck!