The Joy marriage was horrifying due to her age and apathy. I think JD grew a (small) set and married who he wanted, when he wanted, how he wanted. His allowing cameras, etc, was his concession to the “product.”
My hunch is that Jana is being kept for JB and Michelle as caretaker once her child rearing duties are completed. JB is too selfish to allow her an autonomous life. Michelle is just a see you next Tuesday.