There was a Monk TV show about this sort of thing.
I liked the part in the article where they were in a long-term, committed relationship. Then near the end of the article they write ““He set out to visit a few of her known spots where she would party...”
There was also a Colombo episode where something similar happened. The stupid lottery winner trusted a business associate to cash the check and provide the lion’s share of the money, so that his about to be divorced wife (not related to the win) would be frozen out. The associate killed him.