...but do not think any Jews have utter contempt for their beliefs (beyond the standard non-belief in the divinity of Jesus)?
Maybe I am misreading the question, but I don't understand very easily what it would mean to have contempt for a belief.
If you have contempt for it, why believe it?
If you meant having contempt for a teaching or a practice, I guess my thoughts run in pretty much the same direction. If your religion is asking you to do something that your conscience is desperately rebelling against, you should put some serious examination into why you are following along (with that particular practice/teaching).
Maybe ask outside (of the religion) perspective on it.
Get a second opinion, like you would do for a doctor.