I know what you mean. I had an incident with a highly respected bass builder, that dragged on and I was being treated as a complete moron.
Even when everything was put right (only when another luthier got involved and asked the guy in question to behave and stop being a ****), I had such bitter feelings towards the end product, when somebody played it, loved it and asked me if I would ever consider selling it... I snapped their hands off for their low ball offer. It never got used because everytime I saw it, it filled me with rage due to the bitter experience I had had with such luthier. It's a shame - because I quite like his basses... but it seems like I'd never buy anything else from him now.