I'm 49. My bikes are about 35 years old. I would spend the money to fix your bike. I would keep that bike as a backup and buy a more appropriate bike as your main bike. I would certainly buy a couple of tools and learn how to fix a flat tire on your way to work.
There are a lot of reasons to have a backup bike. One can be in the shop. One can have snow tires. One can be for wet conditions. If one is stolen or crashed, you're OK. If you wake up to a flat tire, you're OK.
While you're at it, start literally making friends with your local bike shop.