When I first went to secondary school (this is for ages 13-16), I joined this new club thing. So the club held a orientation camp in school for the newcomers and we were told we could leave school to get our own dinner. I followed a group of my new "friends", headed off to a nearby mall and decided to eat at a KFC. They told me to save a spot for them while they ordered their food first. This KFC's L-shaped so from where I sat, I couldn't see the cashier. I waited and waited and waited, trying to ignore dirty looks from other people who eyed our seats. I got suspicious, finally got up, turned the corner and realised they were gone. Pretty much abandoned, I ate my dinner alone and walked the way back to school alone, just wondering why did they do that. I didn't do or say anything mean, I was pretty much a shy and quiet kid. Ran into them back in school, exchanged glances and didn't say a word. It isn't really much compared to what I've seen in this thread but to this day I have no idea why you would suddenly ditch someone like that.

Quit the club a year later.