。。。もう、意地悪な御方。 ...mou, ijiwaru no okata. ...sheesh, you are a bully sir.
Retaining respectful speech "okata" and the specific exclamation "mou" indicate that the connotation is closer to "sigh, it can't be helped :)" rather than being actually fed up with his bs.
Couldn't come up with a better translation, but felt that the existing line "...you, sir, are the worst" wasn't quite right.
"...After everything you did, I was finally able to sleep well again. I wanted to thank you once more...""But you're awake right now.""...Gee, you are such a bully, sir"