I have seen Internet addiction in my own Home.
My wife started World of Warcraft, lost all social contacs outside the game, stopped eating and drinking, lost 25 Kilo.

I forced her to got to work, her co-workers helped to feed her, after six months she spend outside of working and 4 hours sleep at most 15 Minutes a day away from the game.

After two years I quit and gave up.
She is still playing and doing nothing else.

Internet addiciton is real.