At church when I was fourteen, and again when I was eighteen/nineteen, there were no other teen girls. I was the only one! That isn't too unusual, but to hear some people talk you would think I would have really struggled with loneliness. Now that I've thought about it, I realize that loneliness was never an issue for me. At all!
I always was friends with everyone at church. I tend to be rather quiet and un-needy, so when I enter a room with a bunch of people, I usually try to talk to the person who looks the most neglected and needing a friend - whether or not I know them - and be a friend to them, trying to cheer them up. The result was normally an immediate new friend, and honestly, a friend is a friend no matter how old or young!
So if you're feeling lonely and want someone to reach out to you, try doing the reaching out yourself and see what happens!