Breaking into

One day I go to the Internet, namely on the site "VKontakte". The password does not fit, well, I think maybe something is wrong there. I go to the mail, similarly. The most interesting thing is that on Mail and VKontakte passwords are different. Immediately I realized that the case is unclean, hacked. I create a twin on VKontakte to write about my problem in those. support and see that my main page is Online. I start to write, but not immediately on the topic of hacking, but for the beginning - “hello”. A few minutes later I received the answer "rezar.ru DPKJV" I guess that in English font it is written in Russian letters there is a HANGING. I am writing - “return the page”. It comes to me - “I'm sorry, the guy ordered you, the first break-in and damage to the page for 30 minutes, a second break in 14 days, a break in Vkontakte, mail, ICQ.” Quickly I go to ICQ - “Connection is Impossible”. Here I answer those. VKontakte support. I give them my problem, they return the page to me, I change the password. And I see that on my page, they have already pretty worked, deleted many friends who were sent out - messages with insults, all the information was deleted. Suddenly an entry appears on my wall - “I didn’t recognize the new password,” and this is despite the fact that the page was re-registered with a new soap. Following is the second message “I play in WoW, you throw off the screen of your slave. the table? ”I quickly log in to my WoW account -“ the password is incorrect. ” I understand that the only way out is to reinstall Windows, with the format of all the data.
I format, reinstall, return WoW through the same ones. podderzhku, I create a new soap, Asya, Vkontakte page. It seems 3 days everything is calm.

All this happened when installed - NOD 32 (license), COMODO Firewall, Trojan Remover. So the system was highly protected. There was no direct access to the computer except for me.

Help clarify the situation. How could this ever happen? Maybe a trojan or something?