You make me laugh but I am laughing AT you

I met a person a few years ago who taunts me almost every day and hides behind their computer screen to throw bombs across the internet and into my home.  I must refer to this person as a "chat troll".  This one takes every comment you make and tries to turn it against you.  Be it you may say you bought a new robe.  This person will find some way to attack you incessantly about that purchase.  I have been attacked by this person numerous times regarding whether or not I am a 'practicing' doctor.  Its actually quite funny, but I have had to be harsh with this one.  They have crossed the line of decency and orthodox ways many times.