Damn. Maybe spending 100k on the wedding alone set off alarm bells for the guy.
I'd call off a wedding that cost $100,000 too. I don't want a 30 year mortgage to pay for the stupid wedding.
My way of thinking...$10k is MORE than enough for a wedding.
Anything more than that, and you're getting into little-girl-princess-idealized-stylized-fantasies-and-not-the-celebration-of-the-union-of-two-families-and-well-wishing-for-their-future territory. You can't be 20-somethings and starting off your life together with $100k of debt.
If she's a trust fund heiress, then she can eat it.
If he's a trust fund heir and agreed to the costs initially, then he should eat it.
But if he just decided that she was nucking futs and realized it more and more as she demonstrated her inner Bridezilla... good for him.