What’s the possible relationship of the two speakers?

Harry: Oh, dear, tell me what’s on the TV tonight.
Sheila: Don’t ask me. You know I never watch it.
Harry: I know you are always busy. What are you busy with now? Knitting socks again. I wish I could be as free as you.
Sheila: You actually have more free time than I. But you waste it all watching your television.
Harry: No, that is not a waste of time. I can relax a lot when watching TV.
Sheila: But you can’t learn anything from it. You just sit there and stare at the screen.
Harry: Of course I can learn. There are many educational programmes.
Sheila: But you never watch them. You either turn over the channels or get to sleep whenever an educational programme comes on.
Harry: Don’t be so critical. I need to put my feet up for a while after work each day.
Sheila: I like putting my feet up, too, at the end of the day, but I like doing things while I rest.
Harry: Dear, as I’ve said many times, we’re different. There are two kinds of people in the world.
Sheila: I know. Those who are never happy unless they are having something to do. And those who are never happy unless they are doing nothing.
Harry: So, you just go on with your knitting, and I can watch TV.
Sheila: But I still want you to be well-organized and not to waste your life.