How do you deal with rude coworkers?

On Monday I was 17 weeks. I posted these pictures on my social media, all proud of my new little bump.

I was at work yestersay and finished up my shift at 230, the next round of staff were coming in at that time to relieve us and one of my coworkers, who hasnt been there 2 mins yet, looks me up and down and says, "so...you come to work and you dont look as pregnant as you do on social media?"

My jaw must have hit the floor.

I didnt even know what to say to that other than,

"...what?"

I keep thinking about it, I dont know why its bothering me so much....I'm not faking my bump. I still feel hurt and emberassed by what she said though.