This happened about 2 years ago, when I was still a noob that didn't know how to speak proper English (I live in Belgium).
I started to play the game as a night elf druid. Because of that, I had a quest to go to the spider cave. I kept dying there, and eventually a female nelf hunter passes by, and offers to help me. We team up, and chat for a while. She turned out to be a lovely person. Of course you can't be sure if it's really a she, but I assumed she was. After all, why would you lie about your gender? So, we chat for a bit. Eventually we end up adding each other to our buddy lists. Since then we did everything together, and we liked each other. She really told everything to me, about what happened at school, about her parents, about her general life. It seemed she was pretty lonely, and looked at me as someone she could tell everything (I am such a person in IRL as well)
After a while, about 2 months later, she asked for a 'hug' (/hug emote). I was like, wtf, what means 'hug'? I just said 'yeah' and ignored it. Although a few days later, she asked it again. I ignored it again - I was too ashamed to tell her I didn't know the meaning about the word, since she was really good at English (she lived in Norway). And I didn't bother to look it up because I didn't think it would be important. At that point we were close to soul mates, we really knew everything of each other and spend all our time online chatting with each other. This continued for a while, until all of a sudden she disappeared.
She just logged out and never came back.
I'm currently nearly having tears in my eyes as I'm typing this, really. She meant a lot for me, even though I've never seen her IRL. I don't know what happened to her, and if she's still out there, if she remembers me. I know I'll never forget her, and when I'm in a depressive mood I hurt myself by asking why I didn't gave her that 'hug' and what happened to her.