Johnny did his best not to laugh, it wasn't a funny situation and Mary wasn't making a joke. He knew that she was serious in what she was saying, and her worry was a valid one. There was just one thing.
"Mary, you guys are made to hunt, yeah. But you hunt creatures. What happened to you was done to you by a human, and you've told me more than once, as Jo has told me, that humans are a different thing altogether. Humans are my thing. I know what to do with them, and I know how to handle them. You can't take what happened to you as a sign that you're losing your touch."
He didn't get up off the bed, even though he really wanted to. Mary needed to have her space while they talked about this, and that was clear. Johnny very much desired to walk up to her and wrap her in a giant hug, though.
"You're comparing your personal experiences with a thing that you've never been through. It might be one thing if you'd experienced Hell and then this. Then you could say it was nothing. But you only have what you know to go by. And this was pretty fucking horrible. Don't sell your feelings short."