Why is she so nervous around me?

Ok so, I have known this girl for over a year, we are dating basicly, but we never made it official, we love each other, and I mean it when i say it to. There is always so much that is so weird that happens between us, for instance, when I text her or call her, she is in the middle of calling or texing me, and vise versa. She has dated alot of guys and has sang in front of a huge crowd, and is not nervous person, at all. But she says that for some reason I make her nervous for some reason, and when we get close she gets really nervous. She said she cant explain it and I was wondering if there is anything else to it other than she really does love me. Like if we are meant to be together, cause we have never fought or argued, ever. We always make each other feel better. It crazy? Help?