Most Helpful Guy
I think that it is 5% that stay forever alone all their life not by choice. I tried researching but apparently google doesn't even know :( I feel like it is a low number because at some point in your life, there is most likely going to be one person who will actually ask you out and you say yes. (Granted it may not last, but it at least means you got promoted from forever alone status :D)
As for who is more likely to stay forever alone, it is hard to tell. Men tend to have the issue of gaining confidence and stuff, while women tend to have the issue of waiting for someone to ask them out (and it never happening). If I had to guess, I'd say men, just because if you get into the mindset of never asking someone out, a woman is less likely to ask you out. Then you're stuck in single pringle life.
Geez, the thought of being forever alone is kind of scary D:
Most Helpful Girl
I think the percentage is actually low. I don't have any real statistical data, but I think majority of people would at least date in their lifetime. My uncle didn't date his whole life (I don't know his reasons), but when he was in his 50s, he met a woman and they got married 3 months later. So maybe some are just really late bloomers.