How can i talk to her?

[obedientnose268]

You should try talking to her if you see her, just say hello, and ask her if she remembers how to do something simple. (like, "how am I supposed to do a cartwheel, again?")
If you don't see her, send her a fb message. Just say you saw her at gymnastics and thought she seemed interesting and that you wanted to get to know her. You'll probably get a message back from her..
Don't be sad if she dates this other kid, though. There are lots of girls out there you're going to meet.