I know a gay couple who kept their own separate apartments for years. They'd take turns sleeping over at each other's places, but spend a few nights a week alone. It was a formula that worked for them, until they finally decided to take a new place for the both of them. They're still together.
I know another gay couple together for 18 years, own their private home, and who sleep in different bedrooms. They're in bed together for sex only, or when a guest takes one of the bedrooms they use. They're a very stable couple.
On the other hand, I hate to sleep alone, sleep best when there's a man next to me. I've mentioned the bed scenario because that's the one issue other gay men most often tell me is the main reason they resist having a partner: they don't want to lose their private space in bed. Whereas I feel lonely in a bed by myself and sleep poorly, at least without a man for whom I have special feelings (sleeping with a total stranger is much less comforting).
Perhaps related to your research, I've thought about which of the 2 old adages is correct: "Birds of a feather flock together" versus "Opposites attract." One would assume both can't be correct.
But in a way I think they can be. For me and other men I know, most fundamental interests must be the same to get along over time. If you can't sit together and enjoy the same movies and TV shows, or listen (tolerate?) the other's music, and can't live in the same style of house, go on the same vacations, etc, etc, then you don't have a lot to share and enjoy together.
On the other hand, when it comes to functional interests and abilities, differences can be beneficial to a relationship. One guy likes to cook, the other doesn't (and too many cooks in the kitchen can be a recipe for disaster). One is the fixer-upper, from car to household stuff, while the other is all thumbs but knows how to decorate. One does the laundry & ironing, the other the yard work, and so it goes.
Together they make a team, that covers all or most of the daily requirements of modern living. Would that be your interdependence? And yet I also see some autonomy there, because each member "specializes" in the things that he does, and that his partner does.
And there are discreet borders within this interdependence. Ask my partner that if I try to muck around in HIS kitchen when he's cooking!
So to answer your question, I see some of both the "we" and the "I" just like there's a bit of the 2 old adages in most relationships, at least for gay couples (I note your question does not specify straight or gay). I'm sure "pure" interrelationships exist, but for most men I think they can be both interdependent, while retaining areas of personal autonomy.