Oklahoma Justice

Two cowboys meet. Fall in love. Set up a ranch in Oklahoma together. Raise three kids. Spend 25 years with each other. One cowboy dies. He leaves everything to the other cowboy in his will. But he forgot one of the witness signatures. Distant cousins come out of the woodwork and seize the ranch, kick the widower off, and then sue him for back rent.

Destroying marriage indeed.

Thanks to the indispensible Towleroad for the tip.