I hardly watch TV at home any more as it is better to watch what I want when I want, streaming over the internet. So why have a TV on board.
As far as watching movies goes, almost any laptop will do the job for you there.
I dare to suggest that the best investment you might make for on board audio and visual entertainment is the best mobile internet receiver (ariel) and service you can find.
Are you sure she is not using the TV thing as an excuse not to go out on the water?

However if it is Bell Bird and Days of Our lives she can't live without, I think you are snookered right from the start.