You do want to make sure you're buying the bitcoin well in advance of any troubles or divorce though. If you have $100,000 in your bank account and suddenly it's gone and you claim you don't have any other assets, it's not going to work during divorce proceedings.
My Father in law is an attorney. They excel at finding that kind of stuff. You could only move currency in small amounts over a period of time.
What happens if you move it all over to bitcoin, keep it, but say you lost it all at an online bitcoin casino? Never getting married but that would be my go to play.
Then you run the risk of gambling charges and perjury if they can prove otherwise.