The reason I appreciate non-monogamy so much is that it is, for me, protection against the airlessness and inertia of a couple passing their own limited resources back and forth, using them up like a shared breath.  It is protection from that.
And it is the excitement and risk of seeing your partner invigorated by someone else and trying to be humble enough to accept the benefit to both (all) of you. It's the excitement of knowing your partner is someone someone else wants to fuck and talk about movies with. 
It's realizing the wholeness/complexity of your partner by placing yourself within the ranks of their lovers, people sometimes confoundingly different from you and from each other, all people your partner loves .
It's locating your ego within yourself, not your partner.
It is meeting someone for the first time, knowing that your partner has slept with them and feeling immediately close to them for that reason.  It's becoming friends with the women who scared you. It is bringing new blood into the family.
It's watching your partner fuck someone else , feeling lucky for the number of times you've been the one whose hips they're grabbing, whose hair they're pulling back. It's watching your partner make out with a person you introduced them to with a look of joy and surprise on their face.
It's allowing someone else to be in love with you, even when your partner is not. It is allowing friendships to become sources of oxytocin--affectionate, profound, and erotic in a way that isn't allowed these days. 
It's allowing your partner to drive across the continent, knowing part of it is the allure of never-met women, part of it is being free from you, part of it is the freedom to be the sole interpreter of their own experiences, part of it is the subjective, censored, poetic version you get in letters.
It is allowing your partner to have desires unmediated by affection for you, by your presence. 
It's locating your ego, distributed  across all your relationships, to your surprise not just a monolith hulking in the space between you and your partner.
1 - Now that that beautiful statement is out of the way, perhaps we can come up with a better term for clumsy 'non-monogamy,' perhaps just 'life.' Hardly anyone manages to have sex with exactly one person anyway.
2 - Hot.
3 - or at least likes
4 -Intimacy w/o jealousy is transitive, I think.
5 - The internet suggests to me that this is a relatable scenario, at least in the imagination.
6 - It's true that almost everything does, after all, lead to sex.
7 - It is protection against that kind of loneliness when you can only be who your partner wants to see. They can see other people.
8 - with slightly different faces and bodies