I don't require sex to feel love, certainly. I do require sex as part of being involved. That said, exactly what meets that need for sex is interesting.
I was just discussing this topic yesterday. A female friend's secondary only wants vaginal penetration. She has had serious medical issues that has removed that as an option for months. She's offered oral and anal and other forms of sex play as alternatives, yet he keeps pushing for just that one thing. (I'll avoid offering my thoughts on that dynamic at this point.)
My wife is not a very sensual creature. She doesn't want near the foreplay that I prefer, so at times I'm frustrated by the lack of long sessions that aren't all about penetration and chasing an orgasm. I can be perfectly happy without vaginal penetration as long as I'm getting a variety of other forms of sex play.
As for frequency, my wife is also on meds that inhibit her libido--and hers wasn't as strong as mine to begin with. That just means I need to look elsewhere if I want an increase in the number of sessions I have in any given week.
When speaking of various forms of non-monogamy...it ain't poly if you're just fucking around.
While polyamory, open relationships, and swinging are all distinctly different approaches to non-monogamy, they are not mutually exlusive. Folks can, and some do, engage in more than one of them at a time--and it's all good.