i just wanna know if i leave for lets say, a few months (6 months tops), would i still be able to log in the game and in the forum using this name?

would i retain it? for how long? ???

Yes, you will STILL be able to log in...

You can leave for as long as you wish, and still come back and log in..
The only way you won't be able to log in is, if TMy deletes yer account, which I doubt, unless you do something...