Far Cry 2. Kinda.
When Warren Clyde, my best bud ever, who I thought was dead, turned on me in one of the very last scenes, I left him for last. I deliberately wounded him so I would be able to look him in the eyes. With everyone I had ever trusted except him lying in their own blood around me I quietly approached him. He was just kinda limping along with that piece of crap pistol he liked to carry around in his hand. I stepped right into his path. He looked straight at me and leveled his gun with mine. I could see the anger in his eyes. He thought I betrayed him, left him for dead while we were defending that bar. I wanted to reach out to him and tell him that he wasn't supposed to go down in that tavern. That I had tried as hard as I could to keep him alive, and that I would've stayed there in that bar shooting Africans all night if I had to, but I couldn't. I went down with him in that bar, and now he thought that I was exactly the kind of person we'd been gunning down since I first arrived and pulled him out of APR custody. I closed my eyes and heard the hammer slam that bullet straight into Warren. I was teary eyed but I didn't have a choice. That was the most upsetting part, and the part that makes me love FC2 even more.