Why would a girl be nervous/uncomfortable when I start a conversation but more relaxed when she starts it?

Anonymous
Most of the time i'll initiate and she'll respond, but she looks nervous so after a few tries, i'll stop. If a few minutes pass without either of us saying a word, she'll come up and ask me some random question it start a conversation, making good eye contact and everything then after i take the initiative, she'll go back to the lack of eye contact and nervousness.

Sometimes we can talk just fine with no pauses but when it happens seems totally random. Usually if one of her friends is around, she will act really funny and take charge and tease me all the time but when she is alone, she calms down.

I like talking to her but how can i make her to relax a little? Its just weird that sometimes she'll be confident and others she is all fidgety, any advice?
Why would a girl be nervous/uncomfortable when I start a conversation but more relaxed when she starts it?
2 Opinion