Ahh glad to know I am not the only one struggling with this (even though I am not glad it makes us feel so shitty)...I like to think that some people come to our lives just like chapters - they have a beginning and an end, and it's no use to force it if you just don't click together. I am able to keep contacting people who really matter to me which makes it all the more painful when THEY are the ones who don't reply. It's really shitty to be at the other end of it, which is why I would like to improve in that. What if I make people feel shitty with my non-actions?
You're totally right with the last comment - it's even worse when you run into those people months later and don't even know if you should say hi