"You cannot create a new life without destroying the one you've got." -Martha Beck
Quitting graduate school is a tough decision. I know of no one who quit who didn't agonize over the decision and whether it was right for them. But when you are finally ready to make the decision of whether to stay or quit, it is easy to delude ourselves into thinking it really isn't a decision at all.
Change is hard. But even harder is saying good bye and firmly closing the door behind us. Once I made my decision I remember the ease with which I was able to tender my resignation, quit the program and head off into the outside world. It was an intense, surreal two week period that after the months of anxiety ruminating over whether I should stay or go felt like flying.
Yet even as I left I chose not to file the final forms to quit. I left the door open, which provides a very smart safety net, but also can keep you from moving forward. I realized a few days ago that I have now been out of graduate school as long as I was in it. Three and a half years is a lot of time in your late twenties/early thirties, and I have to say that I have not regretted leaving even once.