One of the causes of mounting abuse is that the abuser gets frustrated by the effects of his own abusiveness, which he then uses as an excuse for more abuse. For example, you as the partner of an abuser may have become increasingly depressed over time (because chronic mistreatment is depressing), and now he gets angry about the ways in which your decreased energy make you cater to him less enthusiastically. Similarly, abuse may diminish your drive for sex, and then he is hurt and enraged about your lack of desire for him.
