OK. I was asked out by this guy on Okcupid. We went out a few times but something just didn't click with me at first so I took some time to figure myself out. I really didn't tell him why I was being distant (I made some bulshit excuse up about work) and he took that as me losing interest and he started talking to other girls and now is in a relationship. For a while now I've been hoping these feelings would go away so I could move on, but they haven't and I'm stuck in this mess.
You need to do more self reflection. You know you fucked up and now want him back. When he was available you know you could take your sweet time and string him along. But now that he's gone you realize you didn't have nearly as much time as you thought. He moved on. He made a decision and decided you weren't worth waiting for. Perhaps thats why you're so hung up on him. He's got more value to you now than he did before.
Like I said, you need to do more self reflection. Figure out what wasn't clicking for you and why. Learn from this so it doesn't happen again.
Hey listen... u rejected him for a reason... My mother gave me a piece of advice im going to give u... "Always remember - the grass always looks greener on the other side." u think since he is in a relation so is he perfect? maybe the other girl is just a desperate girl who can hook up with anyone? who knows... trust me... your first reaction (gut feeling) about a guy is 90 % right... so leave that douchebag... and wait for the perfect guy in your life...
Evolutionary psychology. A man that has a girl already is more attractive than a single guy with no women in his life. Even a guy with female friends is more appealing to women, because in the back of your mind something is telling you he is worthy of all of these girls attention. And your competitive side wants the recognition of having his attention over those other girls.
That and because you dumped him the idea that's "he" is over "you" is getting to you a bit. It's pride.
And I read a comment of yours. No, he didn't owe you notice of any kind. Were you sucking his dick? Dating him steady? No, you weren't. And you projected disinterest. So he responded accordingly -- don't act entitled.