What horrid people. I think Prudence's reply was just right. I'm not sure what the LW should say to her friend, though...
On the topic of pink - I was never a very girly girl, but I took ballet classes when I was little, and was quite fond of pink as a result since a lot of ballet outfits for girls are pink (or were anyway). And DH's sister, who is the most un-girly person imaginable, has a little daughter who is absolutely nuts about anything pink, sparkly, princess or fairy-themed, and adores wearing pretty dresses. I think SIL is secretly hoping she grows out of it!