She doesn't answer for a little while. It isn't about the Master to her. It's about the fact that the Doctor tried to kill himself. She knows that the issues aren't separate in the Doctor's head though. That's been made clear.

"Fine. Next time you decide you're going to kill yourself, want to jot something down for me? Be a bit less with the panic and outright fear then."

It's a lie. She wouldn't but she wants him to know that to her, this isn't a conversation about the Master.