From a NY Times article about sexual desire-

"For example, 93 to 96 percent of the 655 [female] respondents strongly endorsed statements that linked sexual arousal to 'feeling connected to' or 'loved by' a partner, and to the belief that the partner is 'really interested in me as a person'; they also concurred that they have trouble getting excited when they are 'feeling unattractive'."

Come on, women! this is why we always get made fun of.