How long can you grind?

I royally 'hate' grinding. I'd rather do quests or train/chat with friends. That last option makes me die a lot, but it's not like I care. I'm the kind of person that gets bored easily if things get too repeatitive. I like change and experiencing different ways of doing things.

But on rare occasions, I happen to grind for max two hours. Mostly for 2x EXP events or when training a friend.

Just adding something: I hate it as well when you go on to chat with friends, but they neglect you [when I say this, I mean more than once. It is understandable when you are close to levelling up] only to level. Very disappointing. ;<