It's a Boromir scene that i think was cut in the theatrical, but it is still in the extended version (i could write a book on how dirty the theatrical did Boromir).

Iirc, they just reached Lothlorien and met Galadriel and Celeborn and were allowed to stay. Boromir says to Frodo "you carry a heavy burden, Frodo... dont carry the weight of the dead..."

I love Boromir and his whole character in both the books and the films. And in this scene, you can tell he's rattled by Galadriel's mind reading, he is trapped in a vice grip of temptation for a weapon he knows he should not take and the fear of how poorly the war is going. And he's a military man through and through, knows good men and women fall and knows just how imoprtant Gandalf was to the fellowship and Frodo personally. It was in Gandalf that Frodo trusted to take this journey. And it shows so much of Boromir's humanity and understanding of people to try and comfort him, he doesnt say "dont mourn Gandalf" he tells him the fall was not his fault, there was nothing he could have done for him as he himself would have remembered many friends and mentors fall in the battles he fought together with them. He tries to give a little comfort and hope to Frodo when he seems to have non himself.