One thing to bear in mind, it's really easy to drop from connections on the internet. What you're describing is a common experience, unfortunately. You can have real friendships, but people often don't treat them equally, some people more than others. And it's not a male/female thing -- I've known women to seem close, but change/drop out when something in their real life rises. Oftentimes, for both men and women it means an SO has shown up, so that can be a good thing. Could also be a sudden new job or getting accepted at a doctorate program, something that abruptly absorbs their life for a while, and then when things calm down, they find new ways to spend heir time.
As for the pink fog, it's a good idea to try and slow people down until they get their equilibrium.
It's unfortunate if you think you've developed a connection and they just drop it. Online forums or games are easy to do that with, and the online friends can be collateral damage. Sometimes, they even miss the people they've left behind
It's not unusual for them to show up again. In my experience, only occasionally did something truly bad happen. Sometimes something small.
