Kara and Lee always seemed better suited as friends, imho.

And then Sam came along and it just WORKED. The chemistry between Katee and Trucco was just so natural right from the start and Sam actually seemed to make Kara HAPPY which was something fairly new for her, I think. Sure, the angst came in because with Kara it was always going to, but Sam accepted Kara just as she was and I think she really needed that.

And I adore Katee for pushing Kara/Sam in that final season. I hate the reason she felt like she had to (Trucco's accident) but I'm so glad she did.