I've felt like this twice and still frequently cry about the second one, eight years after selling...
The first was what I'd always seen as our dream home (a rambling six bed Victorian house we'd taken on as a huge DIY project when it was divided into several flats), where DS spent his childhood and we had loads of happy times with family and friends. We threw everything at that house and ultimately made a it a beautiful home...but when DS left for university we sold up as it was just too big/expensive to maintain. I thought we'd never find anywhere we'd be as happy, but at 40ish we were still young enough to start again.
The second came a few years later, after we'd moved around a bit, taking on - only slightly - smaller projects and making them our own, doing virtually everything ourselves, but none really felt right, despite being gorgeous characterful houses (one was a Tudor building that had been taken down and rebuilt elsewhere by a master builder in the 1930s, another was a three-storey Georgian thatched house with fabulous garden).
Then, not really looking to move, I stumbled upon a stunning, run down four bed, detached Arts and Crafts house that was for sale 150 miles away. We collected Arts and Crafts and Art Nouveau objects, so it seemed meant to be - the real 'forever' home which would be a showcase for our collection when restored.
I persuaded DH to view it and we sold the thatched house very quickly. Our dads had both just died (vascular dementia) after years of stress for everyone involved and my mum had Alzheimer's, so in hindsight I was probably not best placed to make such an important decision. We went there intending to move my mum from her (self-funding) nursing home to somewhere close by, but the first thing that happened was I was informed it wasn't in her best interests and they'd object to a move for her.
Everything went downhill from there - our business failed, my mum died and we realised the house needed far more work than our depleted enthusiasm - and funds - could cope with. By then we'd torn out the acres of woodchip wallpaper that smothered every surface (on shelves inside cupboards!) and the house looked far worse than when we'd bought it. In a moment of utter madness when it felt like we had no option, we decided to sell and move to rural Wales. Why?!?
The house went into auction where we had loads of uber-critical viewings from people who wanted to rip it down and it failed to sell. Eventually we found a buyer, lost loads of money (we owned outright, but it still hurt) and bought another (repossessed) wreck in Carmarthenshire that I hated at first sight. I knew we'd done the wrong thing, but it was too late to change our minds. For me, it was the perfect house and we'd totally let it (and ourselves) down by abandoning the old place.
When we were selling the (now fully restored) Welsh place in 2024, my beloved Arts and Crafts house came back up for sale. If we could have bought it back, we would, but it was now at a vastly inflated price we could no longer afford. Instead we purchased another ruin little Georgian cottage by the sea where I should be happy and thankful, but every single day I miss the one that I let go.....