Keep, tidy it up to make safe, run in to ground then scrap it.
I would drive it and save up for a new one in the meantime. Right now you can get new cars for the same price (or less!) as secondhand ones, simply by being prepared to wait for a few months!
That's the problem we have found! When we got car 4 years ago it had taken us weeks to find the right one and though I've googled for same model but younger, (have even looked at same age) there aren't any in our price range. Those that are, either have no tow bar (£500+ we checked!) or more seriously the MOT advisories on these cars is like reading our Discovery several years ago and all expire this month! Our car passed its MOT week before this happened with minor advisories.
I have spoke to insurance company and if we take salvage claim premium goes up £7 a month for full coverage (otherwise 3rd party only) and she must pass another MOT, so mechanic we use is going to see when he can get her in.
Also, spoke to someone who lives in area where it happened, apparently his lady friends car was spun round and written off just up from where I was hit. She didn't have dashcam but the garage did and that caught the other driver. My dashcam didn't see the impact but it recorded the hit sound and the conversation. Now going to buy another for the rear window, but not a pod, a proper one!