nedarim 81

rabbis' sons are notorious for treating the torah and the community like dirt.

and dirty clothes can drive one to madness.

this page asks a great question, often asked in jewish communities. why are rabbis' sons such jerks? (actually, the question is why Torah scholars are born to paupers and not to Torah scholars) the answer is that rabbis' sons are arrogant, and take advantage of their father's status in the community and don't respect the Torah. Also on this page is the discussion about the importance of laundry, because dirty clothes can cause madness. 

nedarim 80

dirty clothes and cosmetics, and bathing in dirty water.

but why would she choose to make herself disgusting?

a debate on whether or not abstaining from bathing is considered affliction. and if it isn't, then how can her husband nullify her vow to not bathe, or adorn herself. if she vows to bathe in dirty water, or be adorned with dirt.