Have you ever been hacked?

Today I got away from this vicious RuneScape hacker. He had made four accounts and controlled each one and made something like an act in front of me. One pretended to be my best friend. Another pretended to be his worst enemy. But over all in the end I managed to find it out and secured my account in time. Has this ever happened to you? And if it has how do you deal with hackers? Cheers! Thok