Dear Mary: What do I do now I haven’t sent a thank-you letter?

Q. Over New Year I stayed with a man who combines being a generous and exciting host with a punctilious need for swift, hand-written appreciation. I had every intention of writing as soon as I got home, but my parents said an email wouldn’t do. However, since we were collected from the airport I didn’t have the address and postcode (he lives abroad); also, I didn’t know what his correct title was for the envelope, and I didn’t know what stamp to put on. Then, when I finally had the information, I was told, ‘He gets even more enraged by late letters than by no letters at all.’ I am sure you will understand how the letter just didn’t get written. I am about to meet my host again at a dinner in London.  How can I explain that my failure to write was no reflection on how much I enjoyed the house party and that I would dearly love to be invited again?
— Name and address withheld

A.