How can I get confidence before I lose the cutest guy in the world?

I met a really cute guy who was also very smart, nice and just perfect for me. We were inseparable at the party. He asked me to stay on and then give him a ride home and hang out. I felt insecure like maybe if he spends more time with me he won't find me as attractive (he seemed out of my league). A few hours after I left the party he texted asking if I was going to come back for him, I just ignored it. A couple days later he texted again asking if I wanted to hang out, I said I couldn't that day. Then he texted twice more and I didn't respond and now he stopped texting. I don't have the confidence to see him but then I end up all alone while all my friends are in relationships. How can I get some confidence????? I'm home all alone on Halloween bec I just don't feel as attractive as all the other girls and think a guy must not be sincere when he asks me out.