Sold my legacy years ago because petrol was going up so much in cost, and bought a 1.6 impreza.
It just wasn't the same even though it was still subaru, and 2 years later, I bought the 2.0 impreza I have now.
Though this sounds daft, you might have to sell your car to realise that you really should have kept it...and then you'll know what to do the next time. You're probably torn between the high cost of ownership of a subaru vs a regular car. You might need to spend a while driving a regular car, and see if you are content with it, or do you need the rumble back in your life.
Think about the economics of the situation as well. Diesels aren't all they are cracked up to be. Some of them aren't that great to drive in slow heavy traffic because they're highly geared, and a high proportion end up with turbo trouble etc.
Also, if it is that you want to get a newer car, and say you need to put 3k with what you sell the impreza for and get a newer diesel...............are you really going to make much of a saving? A lot of the saving will be cancelled with having to pay for the newer car. I've seen people (at work) trade in their car, back it 10k so that they only have to pay €190 motor tax instead of €390. The 10k would pay for a lot of petrol/diesel if they kept what they had....
But it's entirely up to yourself, Eanna. You have to do what you need to do,....each to their own. You can always buy another subaru, and best thing is you know where to get help buying one.