Odds of Hanging On
As said earlier, most Operators retire from the military altogether after less than ten years. After spending years being deprived of sleep, flown to the worst possible conditions imaginable (even worse than staying in line all night to buy tickets for The Dark Knight Rises), and seeing your friends blown away around you, the job takes its toll.
There are psychologists assigned to deal with Special Forces members due to their unique stressors and the horrible, awful, gut-wrenching things they see and do. But even with this type of support many don't make it. This may end up for the best, not only psychologically but financially as well. Private security firms pay former Special Ops guys in the mid six figures.