stolen password?!?

I recently had someone on my buddy list (aim) tell me that someone had been on with my screen name and was harrasing them. I added this person to my list and asked him/her about it. The person then began to swear at me, told me that he/she had stolen my password, and began harrasing me. I blocked the user and changed my password (which I don't know why I didn't in the first place). I am assuming this is due to something that had happened to me before: I was using a comptuer at the college I attend and had loaded trillian (a program that can load all of a users buddy lists and msn lists and such into one window). Well one time someone had signed on to a computer that I had used it on, they used it, and our buddy lsits merged. I'm thinking this happened, but I am unsure, as the person spefically said they stole my password. I am wondering, is it really easy to steal someones password? I had never given it much thought as I have no need for it. But it reall worries me. I don't believe I have been overly careless with my personal information, but if I have, I am thinking I am in big trouble... although this has been the only area I have thus far seen the problem, with aim. It seems by now (it's been maybe a week or two) this person would have started to mess with me a bit more; his attitude was very malicious.

How did your friend know the attackers aim name?
Just doesn't seem logical for someone to take over an account and announce who they are...

Most instant messenger account takeovers are an inside job, meaning its usually one of your friends playing around... this doesn't sound true in this case, but certainly something to think about...

Changing your password is the best defence... and don't forget the best password rules... I generally follow: at least 7 characters, containing at least 2 numbers... no dictionary words or proper names.

That's a good question, about the aim name. And I am fairly certain it is someone nearby, possibly a friend, but the person was so ridiculously mean and, well, almost incoherent, all the person said was insults. The few things that I did pick out though are "you call yourself a nerd" (which, if I DO, is pretty jokingly, as I really don't think I am, in the typical sense I suppose... eh my opinion of a nerd is someone that is reallllly antisocial as a basing of their nerdiness, but eh, it really is unimportant), and he/she mentioned the college I attend (apparantly as an insult of some sort). So, apparantly this peson is familiar enough with me that he/she lives in this area, and seems to think I am a 'nerd'. So, a friend? Can't think of many... well I mean they all know my password (haha which I am finally faizing out, thanks to this heh), but none are this, well, stupid. Thanks for the advice and opinions though, it has help to alliviate some of my fear...

Spoken like a true nerd... =)

Ya, perhaps having all your friends know your password isn't the best idea anymore... I figure so long as you've changed the password, you should be okay... I also recommend you change the password for any other place that used the same password you had for AIM...

I remember way back in high school I had the same password for everything... it happened to be a band name... and one day I wore the band's shirt, and my friend happened to guess my password... ever since then I've (1) never used a band name, and (2) never let my friends peek over my shoulder when I type passwords... =)

I also generally try to follow the 7 characters, 2 numeric, password rule... also no dictionary/proper names...

Cool random password:
ia1tfmp5

Based on: I am one to forget my passwords... ;-)

don't bother trying, as i've never used this password before, and i don't really plan on starting... =P