I agree, I can see why people don't stay the course. You start off thinking 3 mths, maybe 6 mths then it goes longer and your like WTF, I am out.
I think if anyone chooses to stay the course it is because they are so comfortable and confident with themselves which enables them to handle the rollercoaster good and bad. They can also can keep their emotions in check which doesn't push the spouce to far away.