Oh man! I feel you on this one. I started this journey as a 42B (lol - you'd think if I'm going to be as big around as a 42, i'd have a little more boob, but no...) Almost at goal, and I'm a 36B (still a B...but a slightly less full one...). I guess the buggers aren't going to change size...which is a good thing...didn't have much to lose from them in the first place.
My partner has gone from a 40DD to a 38D as well...it doesn't bother me any. The difference isn't all that noticeable! your husband will adjust!
Congrats!