The truth - for me, at least - is that stuttering is not what holds me back. I'm very shy and quiet and I used to attribute that to the stuttering/blocking, but I know the former came before the latter. There's many times I'm embarrassed by my stutter, for instance when ordering food, talking to someone I've just met, talking on the phone. And I guess it does hold me back a bit. But for the most part its incidental. I wish it wasn't there, but I know that I could be however I want to be, even with the stutter. I've met two other stutters, both more severe than me, and they seemed unembarrassed and ok with their lives.