I have the opposite opinion in that I think that sexual harassment cases involving exes in the work place should almost always be thrown out, but alas...
It's nearly impossibly to date someone and not sexually harass them in some way. It's doubly hard to break up with someone and not sexually harass them in some way.
Considering most of her allegations are words/phrases that he called her, and considering many people call significant others very bad things when they are breaking up, it's almost impossible to draw the line between sexual harassment and break-up banter.