There is enthusiastic, and then there is Taiyou (and class rep).So Yuri never meant for her words to hurt Hiiragi. However, just saying those first words meant that Hiiragi never got to look at what her lips were saying afterward.
Yuri lost her friend because she didn't think of what she was saying. How will Taiyou get Yuripee and Hiiragi back together?
Also, I find it funny that Sakura didn't use Yurippe. She's enthusiastic, but I guess not that enthusiastic.