[ThirdSight]

I wouldn't say forget about him right away. You're in a tender spot right now, so take anything said with a grain of salt, and do some thinking before you do anything.

Quite frankly, he doesn't know what he wants. It may not be the girl he's missing, but what he saw in the girl that he misses; in short, he's missing the things that switched him on so to speak, and made him more attracted to the person he was dating. This isn't necessarily true, but usually when someone goes missing someone like that when they're in a relationship with someone else, they just can't make up their minds. Otherwise, he'd be stuck on you like white on rice.

Here's one solution: confront him about it, and tell him to make up his mind. No point in getting upset about whatever decision he makes, just so long as he makes one; at this point, he's just not being fair to you whilst he's taking his time making up his mind.