Mostly because I'm busy with things. Work mainly. Some aspects I do not enjoy, but it is still fun when it comes to the technical bits. Enjoying those!
Off work, life consists of quite a bit of physical training, something I have come to enjoy too. That is complementary to another habit of mine: sleep. I'm sleeping sufficiently early to wake up for exercise these days. That is a luxury for most people. Ask yourself, when is the last time you have had a good sleep? People are usually so sleep deprived these days, which is sad, literally.
It does mean I sacrifice other material enjoyments in life; TV watching, net surfing or out having a few late night drinks with friends. I don't miss them much, perhaps just a little bit on the socialising. But there's no point in hanging out late in this country; people tend to go overboard with their drinks - there'll hardly be any sensibilities left for meaningful interactions after late ... but I think a lot of people here will digress!
Life is coasting along. It does feel a little aimless sometimes. But then again, what is there to be aiming for? Does it matter whether if you have not done the gazillon things that you wanted to do? In the long run, we are all dead anyway. Maybe that's not enough, for we need that epitaph to survive us?
Well right now, it is enough.
For myself, keep writing. For my friends, keep in touch.