Atlantis Slash: I know I want it, I just don't know how

I haven't watched much Atlantis lately, and I haven't talked about it all. Why, I asked myself?
I like the show, I like the characters, I even stopped calling Rainbow Rainbow, well, most of the time anyway. Many wonderful writers write Atlantis slash. Most of them are on my friends list, so it's not as if I didn't know where to look for the fic.
I just haven't felt like reading it.
The problem is that I don't understand the characters.
John and Rodney have sex. Lots of it. That much is sure. But why?

When I watch Stargate, I see Jack and I know that he loves Daniel.

I see Daniel, and I know that he thinks that Jack is a pain in the ass whose idea of retiring and settling down with Daniel, complete with christmas tree and family dinners, is way too much commitment for Daniel. And that Daniel will keep coming back to Jack, no matter what, because the alternative is unthinkable, because it's always been about Jack, even when it wasn't.

I see Teal'c and I know that he thinks they are all terribly cute when they are young, and btw, did I mention he is having a midlife crisis where he wants to be the big Jaffa hero who has a groupie girl on every planet, because his wife's dead and his son's a grown-up, and his God has a snake in his head, so could he please have a life now, preferably one that involves group sex with the rest of his team on the weekends?

I see Sam and know that she should get over the whole girly marriage-children-cookie-baking thing and just accept that she is meant to have kinky leather sex in biker bars for the rest of her life, so that she can sit in the briefing room on Mondays, look at Jack and think: "I got laid, did you?", because it will sure make her happier than anything she does at the moment.

See, Stargate, no problem. I know the characters, and I love them.
(though I am aware that my version of the characters may be a bit different from yours.)

( Atlantis is a lot more difficult. )

See what I mean? There is no love. The one certainty in (Stargate) life is that Jack loves Daniel. I haven't found the Atlantis equivalent of that love yet. And it's driving me crazy, cause here they are, having more sex than you can shake a stick at, and I just can't figure it out. What if tomorrow Ford falls in love with Rodney? Or Weir starts an affair with Beckett? It could happen. There is no rule that says "Jack shall love Daniel and no one else, for the rest of his life, even when he is making out with Jonas in the Pel'tac."

I think I need to watch more Atlantis, maybe i'll figure it out then.

Meanwhile: who wrote that Atlantis fic from Rodney's POV, where he thinks of John as a sex god? I'd like to read it again, see if it clears thing up a little bit.