Compliment her

"After Lord and Lady Royce's visit at the beginning of the month, I didn't get a chance to talk to you. You were the perfect host, and the reception you threw was truly spectacular."

Her stony facade falters somewhat, "Th.. thank you, Jon.

You decide to push your luck.

"I have to say, too, that all those who decided to comment on the beauty of Lord Royce's wife, even if it were to bolster his ageing ego, were mistaken. Father should have made it a point to tell those in attendance that the real beauty in the room was you, my Lady. You always are the shining light of a reception. Lady Royce has not even a single ounce of your grace or beauty."

"I beg your forgiveness, if it's my inclusion in this household that has put any strain on your relationship."