I think the opportunity for catfighting within some sort of love triangle was ME2 where you could pursue multiple LI's, but BW took the smart route and made them too professional for that. (Though I wonder what with a certain character and their "cuttlebone" comments.) After all, it would be kind of petty to catfight while on a suicide mission..which involves galaxy-saving and other important things like that.
So, too, it will be with ME3 I believe. Garrus himself has already risen above doing such things and doesn't even
like dealing with that stuff. "I don't want to be dealing with some stupid love triangle." Garrus is too professional for that...the man's grown beyond that stage, I think, so such wishes will have to remain in the realm of fantasy.

And Samwise was one of my most favorite characters in all of LotR. Dude's a real hero and a real badass.