I'm a man in his 20s working in a research center in one European university and I'm wearing a longer beard and completely shaved hair (my uni doesn't have any dress-code or something like that). Everything is good here, except one thing.
Everybody was ok with my appearance, until one of my female colleagues started publicly complaining about it. At first she usually put it as a joke, but lately, she started openly insulting me in front of other colleagues with "just shave that, you look terrible" etc. To make it even worse, she started to gossip about me with other colleagues and some of them came to me with similar appeals.
Today she confronted me again when I was drinking my coffee in the kitchen and she told she will make a petition and gather a lot of subscriptions for this.
To be honest, I feel very uncomfortable because of this and I don't know how to deal with this situation. Up to this day, I was trying to overcome it with smile and joking, but I feel really insulted every time.
I can't see any way out of this - I feel it's really silly to argue about my beard and haircut with people in their late 20s in a math department. Moreover, I don't want to appear aggressive or argumentative in comparison with a petite woman (no offense, just description). But of course, I don't want to be insulted, either.
How should I deal with this?