Dating

So, for people who is single now, let's face it, are you single bc your self-confidence is low or bc you are afraid of relationships, people, rejection tc? I know some people don't like relationship bc it's inconvenient, but I kinda feel that they are lying to themselves (maybe?)

So I was asked out by a guy who is really fit. Like, he has abs. Now, I'm not overweight, and I've learned to love and accept my body the way it is, so I'm comfortable with myself for the most part, but I'm nervous about what he will think of me since I don't work out. I mean, I eat well, and am healthy other than the fact that I'm not very active. I just. I don't know. This is the second time I've ever been asked out and the first time ended up in disaster. I just wondered if anyone could give me some advice.