What exactly happened with her and Jon Yount? I know she was sentenced to whatever jail time for helping him escape, so I am assuming she had an affair with him.
Are she and her husband still together?

Chester Brodbeck passed away in 1995 at the age of 54. Based on the obituary, they were still married when he died. And based on the picture of their shared headstone, she is still alive

https://www.findagrave.com/memorial/20923779/chester_granville-brodbeck