Quiet death of hobbies

As those who know me best, it's time for my fall malaise. For those who don't here's a quick synopsis: Every fall for as long as I can remember I tend to get moody and introspective. When I was younger and more volatile it would present itself as depression and epic nostalgia. The irony is that Fall is my favorite season.
In the last 5 years or so the fall malaise has been more subdued, more introspection, then depression. And this year is continuing that trend. Perhaps it's growing older, perhaps I'm just busier and generally fulfilled. Whatever the reason, this year has already shown me a couple of things about myself I hadn't realized. So what is the result of this seasonal navel-gazing?

I don't like cars anymore*. Or motorcycles. I'm no longer keen on learning how to build everything. At some point, I stopped being a 'reader' (I blame college). Single-player gaming leaves me cold. I'm never going to learn all the skills of the ninja.

Basically many of the traits that used to define me (in my own head, anyway) don't fit anymore. It's an odd feeling. What do I do with all the tools and books and material I've accumulated over the years? Do I really get rid of that sweet '60s Cafe Racer gas tank that never found a frame? Can I slim down to one set of sockets? Should I?

But for me the bigger problem, is that I feel like I don't have 'an interest' anymore. Something to occupy my thoughts when I'm trying to fall asleep. I imagine that someday soon, that'll be the house we buy, but until then I feel kind of blank. Hm...