Josh isn't in the same situation as Nick. He isn't a Grimm. As FaceInTheCrowd pointed out, Rolek, his father, appeared not to have been pursued by wesen like Marie was. But then, you probably didn't even read that. If wesen are as different as humans, why would you think all Grimms have to act the same?
The best way to frustrate a cyberbully is to ignore him.