Earlier quoted context omitted.
Why would he make it so personal? What did you guys do to him?
Is it possible that it wasn't personal? That the contract was cancelled because the product wasn't worth it? That the note wasn't extended because he thought the company was a money sink which would not be profitable? That he thought trying to liquidate the good bits was a better way to get his money, rather than a payment plan from a value destroying enterprise? That he sued personally because he felt they might be…
You would be stunned at how often the reasons for events like this are driven by simple narcissism and spite. That's not cynicism speaking, it's reality, and something well worth keeping in mind in any business endeavor.