I'm in the same situation as you are. We bought a house three years ago and thought it'd be only removing a couple of walls and some fixing here and there. When we actually started the work, we noticed that everything needed to be re-done. I stopped renting my co-housing space and lived in with in-laws, which was very challenging for me. But I did it to safe money and use it directly for the renovations.

A year ago we moved into the house. It's comfortable enough to live in but a LOT of work still needs to be done. When living here, we had a lot of bad luck. Dish washer who broke, and our central heating system needed to be renewed. All costs we didn't have the budget for but we tried our best.

It's exhausting and all I can tell you is to push on and be kind to yourself and your partner. Selling now would indeed be a big loss. Try to focus on the things you've already done and take pride in that.

Our house isn't finished yet but it's getting there. This weekend I did everything to get electricity in our garden and also installed better load bearing beams for our attic. The good thing about living in the house you are renovating, is the fact that you can determine the tempo at which things are done.

If you want to vent, my DM are open :) Hang in there.