Internet is full of groups as is every place people exist. What's different here than physical groups is that the structure and norms are forming just now as I'm writing these down, and they are imitations of physical group norms, which won't work. This is not a serious issue, these sure will be eliminated in the medium to long term but what's bothering me is that people are taking these misplaced rules too seriously.
I won't go elaborating on these rules, but all I want to say is whenever you feel down, "un-liked", neglected or insulted due to your online interactions, think again.
If it's a person who makes you feel this way, speak to him/her "offline" if you can. Internet is a nice place for a lot of things but not empathy, misperceptions do happen when all you have is pixels to express yourself.
If it's a group of people, take group dynamics & (probably non-sense) group hierarchy into consideration and re-consider how much you should let them effect your spirits.
Web is a place you come to pursue your interests, have fun, maybe do some business, socialize to some extent, and even maybe build a new life; but I really don't think anyone is coming here to ruin their day.