I think it's great thing if you have a sequence of pretty forced moves, like pushing a pawn down to queen. However, in more fluid situations, I find it embarassing when I guess wrong on my opponent's move and serve up my pieces to be taken.
You should just ignore your opponent's tirade and delete the posts on your profile. Tell the person that you will report them for abuse if they don't stop.
Yesterday, I beat someone in a 1 minute bullet game. I had around 20 seconds on my clock when their flag fell. Inevitably, this guy called me a clock cheat, which I found ridiculously funny as I'd just been beaten by the same margin. He continued to lambast me, saying it was unfair to use resources unavailable to him. I informed him using premoves was part of bullet chess and if he didn't use it he would never have much luck. This only incensed him further. He then spammed my wall, digging into old posts I made, and generally behaving like a very good troll. What is your opinion of premoving and of those who don't use it?