>>3J. : Given how you've dug yourself in against adapting, the daughter-in-law isn't alone in her stubbornness.
I am sympathetic; I'm sure the TV on most of the day you'd prefer not to need your son and his family, and to be able to hop about the house at will. Independence dies hard.
However, you're quick to dismiss the efforts - and expenditures - your family has made to compromise on the TV. And you're also quick to attribute your daughter-in-law's stance to her character, instead of considering that, just as you have concrete reasons for wanting the TV on, she might have concrete reasons for wanting it off.
For example: Even at a low volume, the TV is aural clutter, which annoys some people. It involves flickering light, also an irritant to some. (Game shows = flashy and noisy.) And, further, when the TV is on, it takes a room that might otherwise be used for many purposes conversation, hobbies, reading and co-opts it for a single purpose: watching TV. Your daughter-in-law could be - generosity incarnate and still see TV as a blight. Plus their kids, their call.
So, Suggestion 1: Lay off her. She opened her home and private life to you, and her preferences matter.
Suggestion 2: Have your son program anything you want to record, so all you need to learn is access. Then learn it.
I realize you're fighting a lifelong habit. However, watching when you're alone is the perfect, cooperative solution, and you owe it to this family to embrace it.
Third: Since you want the company, stay in the living room as people come home, TV off, with magazines, puzzles, crafts, anything you don't plug in. In this home, that's the inclusive move.