I was thinking weekend away (maybe Spa weekend) or one of those 'experiences ', check our Red Letter or Virgin experiences. What about Orient Express journey? Hope this helps.
We took my Mother on The Orient Express (London to Bath) for her 60th. Absolutely wonderful experience. She loved it, talked about it for months after.
I have the same problem at the end of the month, and not a scooby as what to do. We had thought about a small party but he isn't at all keen and doesn't know what he wants. I could just let it pass, saying he has me, does he really need anything else?