I like my in-laws but surprise surprise, they do get on my nerves at times, usually due to their desire to spend lots and lots of time (they're both retirees) with us, either at our place or their own (they live in an adjacent town), as well as the expectable slate of cultural and political differences. But they're certainly better than I deserve and the thing I probably find most unsettling isn't really their fault: I live in the house that my mother-in-law grew up in so, through no fault of her own, I don't think I'll ever feel like this place is actually mine. It's like being half a tourist in my house. Alas.
My wife hasn't mentioned any ways in which my family have got on her nerves but surprise surprise, they all live on the opposite side of the North American continent from us. Alas.