I empathise. I won’t go into detail here, but 20 years ago I built something that went on to be a major commercial success - after I had been coerced into signing over ownership at the pointy end of a lawyer. For not dissimilar reasons, it’s a lost cause at this point.

For what it’s worth, I just view it as part of the lottery of life. You win some, you lose some, you learn plenty.