What are you talking when you talk with your parents or love partners?

I don't know why, but this question is stucked in my head. I don't have much conversation topics I guess with my parents. As for love, I've never really been in a committing relationship which made me wonder what do people talk about.

For me, it seems like topics get drained by time and I just don't know what to say next, soooooo ya. :)