Wow! What are they doing to make her go so easily? Maybe they have suggestions or tactics that you can use at home. I know, with our son, the more we pushed him to use the toilet, the more he resisted. When we finally realized that we were stressing him about it, we backed off, and he used it on his own very well. The weird thing is that, when we were out at a restaurant or other public place, he actually WANTED to use it! lol It was like a treat for him, and he was excited about it. Kids! lol
Maybe if you just remind her how much you love her and tell her that it's okay if she doesn't use it, that will help ease any stress she may have. Also, have you tried using stickers, charts, or other incentives (bribes...lol)? What about a "Potty Party"? That was his final "push" to use it, because he LOVES parties. lol When he finally used it on his own, we threw him a "Potty Party", with a cake and two of his friends (that are potty-trained). ;) We got balloons, too, and he LOVED it! He got to pick out new underwear at the store for his present. It was GREAT!!!