[hobbes]

I agree with TDOL, if you 'cut off your nose to spite your face' it's more of a pride issue - not in a good way either.

eg.

If you imagine it.... cutting off your own nose because you have had a dissagreement with your face - nobody wins.
Rather than accept defeat and be humiliated, a proud person will look for maximum damage brought on everybody, even at the cost of damage or loss to themselves.

In ancient Roman times cutting off the nose of a man was a punishment for adultery, this practice was also carried out on WOMEN in India for more than a thousand years. Although not directly related to this idiom - Asesh (from India) had the idea in his post that this punishment carried with it a lot of humiliation.