I really probably ought to just suck it up and get a new bike
Well today's ride was ruined before it started. I've been putting up with a bent rear wheel for a bit over a week (it snags on my rear brakes every half-revolution and makes coasting impossible) and the gears have slipped constantly ever since I got it. Today, the front tire developed a giant leak right by the valve tube, so it's now unrideable again. And the wheels are 700x35mm, which for some reason none of the shops I know of here carry, the last time I had to check. I'm going to have to special-order the tubes again. Arrrrgh.