Do we need relationships?

I’m a girl and, to clarify…when I say ‘relationships’, I mean those with someone of the opposite sex – or same, I suppose. Just…a sexual one. I have plenty of friends and love my family. What I have never done, though, is kiss anyone not part of my family. I’ve never had sex or even held hands with someone – and I’m 24.
I’m not unattractive, but I did used to be shy as a kid. Now, I’m much better. I wouldn’t say I’m relaxed around strangers, but I’ve gotten quite good at making friends. And what’s more, I don’t feel any desire to go out and search for someone. I’m happy. Sometimes I think I’m lying to myself – but I do feel happy most of the time, I look forward to things and I can honestly say I love my life. It feels like I should be down, but I’m not.
Could it be possible I’m just different? If I think about never being with anyone, I truly…don’t mind. Do any of you have suggestions as to why that might be?