That's such a good question, and not having them has never really bothered me, but the older I get, the more it begins too.
I have always struggled with friends throughout my life, making them and holding on to them. You are definitely on a back footing when you look different and are not what society deems as normal. You certainly have to work that extra bit harder from the off, and as a kid, when you can't do the normal things that all kids do, its hard to fit in and really knocks your confidence.
Whether I have chosen not to have friends, or whether this was just a result of the continuation of the situation I found myself in as a kid, where not really having any real friends I made the most of the ones I could get, the likes of Sonic, Mario and Pac-man, I am not sure.