"I..." was left for dead. Cloud was left for dead when he regained some sense of consciousness, said goodbye to Zack then finished the journey to Midgar on his own. Zack should know, of course. It was, after all, his corpse that Cloud buried in a place only he knew. But what kind of friend told his best friend he died? That was cruel. Zack had the chance to live again now. He should not be subjected to his unkind fate...
But really, Cloud just didn't have the heart to tell him he lost, and that he was killed for his sake...
"...don't remember," he uttered, feeling sorry he had to pull that card again and on Zack of all people. "I was...groggy then. I don't remember a lot."