The other question to answer is, “Why is he doing this?”
I can’t say specifically why he is leaving you hanging, but I can tell you that when I’ve done it it’s because something else more pressing came up. It was nothing personal against the girl… I just had a lot going on and I put off responding until I had a free moment… and that free moment never came.
But again, there’s no way that you or I could know for sure. The best thing that we can do when we’re in this kind of situation is not take it personally.
It is possible that if you don’t chase him he won’t come back, but it’s much more likely that if you do chase him he won’t come back either. I mean, think of how you thought of him when he was chasing you hard at the beginning. He felt like an option and not an opportunity you needed to grab right away.
This is all my opinion based on what you’re saying, but I can tell you I’ve seen this type of thing before. It’s not easy, but in pretty much every case the best thing to do is to not chase and to not take it personally.
That’s not to say you should be cold or anything, but it definitely wouldn’t hurt to relax, get some distance from the situation and give him some space to come to you.
You might also find this quiz helpful – take the “Is He Losing Interest?” Quiz to figure out what’s going on in his head and if there’s actually an issue, the quiz will tell you what to do about it.
Hope it helps,