I don't think anyone's self worth should be tied to the job. With that said, it seems unavoidable sometimes. There is a ringing of truth to what you say, but it's possible to "not give a damn" about the passengers, move onto the next airline and do great, and never hurt any of your self respect.
It does sound like that's the only thing that is keeping you going, and that's commendable, but there's more to life than how you treat the passengers that you are paid a concessionary rate to fly around after a purposeful bankruptcy filing.
I'm not saying it's open season on passengers, and no one should take out their stress at work on the passengers, but I don't go out of my way to be attentive to the passengers because it is tied to any self worth. I do like doing the "one nice thing a day" for a passenger, although last night it turned into a series of about a dozen nice things, but it keeps my mind off the commute.