E: Equals
Something you are clearly not. However, that does not mean that you're inadequate, unloved, or unimportant. In fact, you're crucial to your hothusband/hotwife's happiness and sexual satisfaction. They love that you worship them and allow them to fuck whoever they wish; they love you for putting their pleasure before yours.
You make their happiness possible and you're so important to their life and your household -- your role is just not that of the man who pleasures them sexually. You do fulfil so many other important roles.
Just because you're not equals doesn't mean that you're not loved deeply and cared for, and that you aren't incredibly important to their life. They may sleep with countless other men, but you're the one who's there to listen, keep them comfortable, laugh, cuddle, etc.