The truth is a defense against slander. If she is a sperg then calling her a sperg is not unfair. Nor is it an act of violence.You playing dumb.
I had to look the definition up because I hadn't seen the word until a couple minutes ago. Part of the definition actually refers to the actions of the individual. Nine times out of ten it will be those actions which draws the mockery.
'Sperg' is both a verb and a noun. It's almost always used for Internet purposes, and to sum up, it pretty much means a person with Aspeger's (or perceived to have it) that gets so dramatically passionate about a subject to the point where it's greatly aggravating to everyone else.