So, it wasn't a hack job by the garage that did in my transmission.
It turns out that Matrix/Vibe 5-speed manual transmissions are notorious for self-destructing. Sometimes as early as 50,000 miles. I basically drove on borrowed time for 100,000 miles. This time, though, there is no repairing it, unless I were inclined to spend a few more thousand dollars having a rebuilt transmission put in. Since the transmission would be a rebuild of the crappy transmission that's already in it, and I'm not inclined to start buying transmissions in job lots, the only thing left to do is to call the Public Television car knackers and have it picked up and donated.
My consolation is that I must be pretty good with a stick shift if it took me that long to break it, right? Right? Throw me a bone here, people.
Unfortunately, I had no reason to look into this until it died or I wouldn't have had the clutch and pilot bearing done, but . . . water under the bridge. Sometimes you just have to suck it up and move on. And sometimes doing that is awfully expensive, but there you are.
My hope was to put off all this until the end of next year, but that's obviously not going to happen because the car is dead right now. Fortunately, there are a lot more big hatchback/tall wagon/small faux-SUV type vehicles available now than there were in 2002, and the features I like are more universal, so I didn't have to make compromises. Flat-folding rear seats, for example, are basically a given. Not "flat"(ish) folding seats, but flat enough to carry stuff or to sleep on if you're camping and a storm blows in. There are even a scant handful of models available in stick shift for pigheads like me who like to do extra work. (Yes, I'm aware that manuals aren't even more efficient these days, but whatever. If I'm going to have one car and keep it until it completely dies, I'm going to get just what I want.)
I'll update when the finalist arrives and I have keys--actually, I think it's a remote starter tag nowadays--in hand, but by the end of the week I should have the rest of the car shenanigans wrapped up.