It's not your fault, [ the Doctor responds with a small smile, as they spot the mall in the distance. The Doctor's taking them right to the food court entrance, it'll be less than a minute until they reach there. ]

I'm only sad because it's my mistakes that make Clara different. She doesn't want me to be sad, but I can't help it. [ That small smile takes on a sad tinge. He's always going to be sad about this. He took Clara, yanked her out of time, made her something strange and different...and most importantly, ignored her wishes. She wanted to die. He didn't let her. ]

We're always sad when we think about what we could have done better.