Right. JA said that there will be tension between the two (Reed and SS). Why?
We don't know. Because SS is the villain of the movie and Reed just happens to be protective of his team, him being the leader and all? Or because Sue brings out the good side of SS (again, see her comment for reference) and maybe, just maybe, Reed misinterprets this for some kind of extramarital activity? I doubt the situation in question is a
real love triangle per se, more of a mix of misinterpreted signals. The last thing we're going to see on screen is Jessica Alba having sex with SS one second and the other with Reed.
But all of this is just pure speculation, and it was quite brilliant for JA to say what she said, we're just doing what they want. They're hyping it up. And yes,
the article mentioned something about a love triangle, but not anything about who's the third party. So all this speculation of SS being some hornball could very well be totally inaccurate. Maybe Sue's new "love interest" (I'm still
not buying the article without a few thousand grains of salt) is Mole Man for all we know. They're just playing with us, because they want us to see the movie. And that's that, really.
//Edit. Oh well, apparently Hiruu beat me the punch. Anyways, we don't know
any details about the so called love triangle, so jumping the gun is just silly.