I have found that the people that post goodbye threads never leave, the people that leave for good just disappear. So see you soon street
That has a psychological basis indeed, Walrus.
Resistance to 'un-care' about a certain thing can be better mastered by switching to something else, or maybe experiencing a new scene, a girlfriend, a job, an inner transformation. And what a lot of so called gamers (but actually anywhere) do when 'pretending to leave or say goodbye from the gamingĀ“ is just pick a different game, which is another why, they all come back one day
But as for the goodbye messages 'I gotta stop playing', it has an emotional appeal, an unconscious way to map if you'll be forgotten, missed, hated, loved, or if it will not make difference, either way you are unconsciously still in love with it. In fact if someone is being forced to stop playing, it will probably boost the vicious for playing, or at least make its longing more compeling, than before.
So if you have to leave, you already know what to do, be strong, focus on the something else you got, let it fade out...
If you are somehow forced to leave for a reason or by someone, bear in mind that you have to want it as well or negociate it better, because just breaking the act, not always means emotionally breaking appart from it.