Unfortunately, your car isn't the problem...as ILUVMILS stated, the inept techs working on your car ARE!
I would too be frustrated if I had a problem and took the car to a reputable dealership, only to spend lots of $$$ and see the problem reappear repeatedly.
This should have been fixed the first time and for good (and for probably a lot less money).
Don't sell the car, there's nothing wrong with it. Find another dealership...