Getting old

What is the generally accepted demarcation of middle age? Is it a set chronological age or is it when certain milestones are reached?

I'm turning 36 in a little more than a month. 36. The age Homer Simpson was when The Simpsons premiered (the writers did manage to age him up a tiny bit over the last 29 years). The same age as Jay Sherman was on The Critic.  I was rewatching the first season of Cheers last summer and the realization struck me that with the exception of Coach (who was only in his late 50s at the time) I was the same age or older than the entire cast. I tend to think in terms of television way too often.

Do previous generations always seem older at the same age to each one that follows? Maybe the cigarette smoke and banned ingredients in food aged them, and the more insulated from these negative influences people were, the longer they retained their youth. The adults of my age group still seem teenagerish in comparison to records of those who were the same age in the past. It could just be the distance that analogue media tends to coat over the moments preserved.

I'm at the age where many of my friends are married and have children; a number of them are already divorced. I went bald young but I'm seeing white hairs creep into my beard; I'm seeing other friends in the same age group embracing their grey hair (and looking damn good). Maybe we learned the lesson that refusing to accept the physical aspects of aging is ultimately a losing battle. Sadly, some of our bodies are starting to turn on us, though it's just as often a case of genetic timebombs going off than poor maintenance on our part. The reminders of our own mortality are becoming more frequent.

I sometimes feel further away from middle age than a lot of the people in my generation, since I'm not partnered, nor do I have any children, and I can't really see myself owning a house at right now even if I could afford it. I know people about five (or more) years younger who seem to have pulled off the "adulting" thing better than I have. Despite this, I often feel like my soul is about 60; this could just be my fondness for post-punk music, though. Maybe I just think more in generations than chronological age. The hippies are now in the age range widely considered elderly, with the punks not too far behind them; Generation X is now firmly middle aged. Grunge was over 25 years ago, Nirvana's Nevermind further removed from today. Babies born the year I graduated from high school will be heading to university in the fall.

I'm seeing incredible people in the world who are doing good and interesting things, people I would like to get to know. But sometimes I think to myself, "am I too old to make this connection?"