This guy is confusing the hell out of me & sending me different signals.?

I don't like him just from your description. If he stood you up without a good reason that means he doesn't care about you, period. It sounds like he's using you or playing you in order to get whatever it is that he wants. If you can go for a while without talking to him and he isn't reaching out to talk to you, then he isn't worth it. If you left him a couple summers back, even if you can't remember the reason, there was a reason, and something isn't how it should be.