Kate has a dit I l’amour you, but to Kevin the guy she married.
She hasn't a dit I l’amour toi on screen to Jack ou Sawyer. In the episode "Every Man For Himself" she a dit "Yes I l’amour him!" when asked par that 'other dude' while Sawyer was being beaten to a pulp - though later in the episode Kate then takes back what she said.
Kate has not a dit I l’amour toi to Jack on screen, but it's pretty easy to assume from their time together off island with their engagement that she must have a dit it to him at some point, we just haven't seen it. It's also fairly easy to assume that she is still very much in l’amour with him, looking on her actions in season 5.
HI LISTEN AT THE END Lost THE 6TH SEASON SHE a dit TO JACK AT THE LAST EPISODE KATE HAD TO GO TO THE PLANE & LEAVE JACK SO SHE SAID:"TELL ME I'M GOING TO SEE toi AGAIN AND THEN SHE KISSED JACK AND SHE a dit I l’amour toi & JACK TOO.IT WAS THE LAST EPISODE JACK DIED IN THAT EPISODE ON THE ISLAND BUT THEY ALL LANDED IN LOS ANGELES CAUSE JULIET COULD BLOW THE BOMB & everybody landed in the los-angels at first they couldn't rem ember each other but then they could & jack & kate were together (jack + kate) so this is truth because it was 1 mois ou 2 months il y a the finally
HII!! No, Kate has never a dit "I l’amour you" to Jack (unfortunately), but he already a dit it to her in the end of season 3!! Kate has, however, a dit "I l’amour you" to Sawyer in the last episode of season 4, when Sawyer was about to jump the helicopter. :/ As a jater I think she was carried par the moment, she probably thought she would never see him again, ou that he could die...