In school you get lumped into the group of people who have no friends. You hang around together but they are never your friends and you never see them again once you turn 18.
At uni you want to make friends, you have common interests, studies, clubs, even try a few relationships, so its easy to fake. But you never manage to 'fit in' or make genuine friendships. After Uni you never contact those people again.
In work, you make a massive effort to be friendly but by now you realize your just not like everyone else, you don't want or need friendships. There is nothing better than getting home, locking the door and pulling the curtains.
You can be friendly, its easy to talk about work things but when someone pulls out a cake to celebrate, starts talking about sports or some award ceremony its time to exit the room. You don't get it and can be bothered trying to get it anymore. Who cares if they think you are weird, you will soon be home with the best company in the world, your own.
The weekends are the best, a whole 48 hours without having to see another person. Thankfully all siblings weddings are out of the way, those big group pretenses are enough to make you scream. Having to be there because you have to be there but really spending the whole day hiding in a nearby bar and then having to lie about how wonderful the whole thing was....
Sometimes some of us just don't fit into the world the way most other do. Does that mean we are weird? I dunno, I just want to be left alone.