"I won't ever ask you to," Mary promised him. The blood made her uncomfortable, the death made her uncomfortable and sad, but didn't he deserve to live just as everyone else did? What was the difference between her eating cow and him eating humans? (Mary knew the answer to that but she ignored it.)
"I'll never make you change," she said, swallowing her doubt and taking his hand. "And if I can't handle it... I'll walk away. I'll walk away and I'll stay away and that will be my failing, never yours."