In Star Wars, Luke thinks he’s got a shot at Leia. Leia basically thinks both of them are bozos. Han doesn’t like her at all until he finds out Luke likes her. If there’s a “triangle” there it’s so simplistic as to be “hey there’s a girl here which of these two guys gets to get her.” That’s good enough to call it a “triangle” I guess, and historically it’s been seen as such but it’s pretty thin, dramatically.

But in Empire: The movie starts with Leia and Han liking each other. Luke is barely there, and when he IS there, she’s using him as a means to get at Han. And from that point forward it’s alllll Han & Leia. There’s no Luke. And there’s never Luke again. His leg of the (really weak) “Love Triangle” is dead the second Leia plants one on him and storms out of the room. At no point is he a romantic consideration for Leia afterwards. That’s borne out by the movie itself, and the behavior of the characters in it, and that’s before you even get to Jedi.