When Playing RDR I had no idea of the ending so:
I waltz over to the barn and see the mission name , "the last enemy that shall be destoryed". So I 'm thinking... wait a sec... Then BANG american army. So I kill dozens then I think right time to get outta here! But then wait... They're getting on horse... what about me? ahhh I see epic final stand.. wait he jut walked out there... deadeye wut?! start shooting. then switches to cutscene and I felt a wave of sadness as he goes down.
FarCry2 had 2 buddy deaths that made me feel sad.
First was Paul Ferenc. I got the game on Christmas day and as playing through it. I got to a mission where I had to ambush a convoy with ma buddy Paul. I'd run out of syrettes so I was panicking but I managed to get them all. I can't see Paul but then I hear him cry for help and see him wounded near a jeep. The options were to pull ou tmy pistol or abandon so of course I pulled out my gun. It all happned so quickly, my character turned and I hear Paul cry out "Mama!" before my gun roars then complete silence. The achievement "goodnight sweet prince" really added to the mood.
The second was Flora Guillen. I knew the score about 3 syrettes and it just wasn't practical to use 3 trying to save her. I pulled out my makarov. She surprised me because practically screamed "Do it!" like she didn't care. After she died I was sat there thinking, surely she'd want better last words? Something more meaningful... maybe even just goodbye, she didn't seem to value her own life and that didn't sit right with me.