While I have not B’H suffered the type of loss you mentioned, I had 2 huge work related setbacks (the type that get you fired). One this year, and the other a few years back, They were of different sorts so I could not learn from the 1st to avoid the 2nd.
But each one changed me in a very profound way. I’ll not discuss the 1st in detail, but the lesson I learnt is a ben torah needs to behave like a ben torah, even when everyone else around you does not.
The 2nd mistake was a business error, and it taught me that when all is said and done, I still have the Rebono Shel Oilam, even when my status quo no longer exists. Fortunatly, I learnt my lessons well, so hashgacha got me back on my feet.
But boy, nothing changes a person like tzaros.