Mason Jar of Hearts Hide a bunch of hearts throughout the house and have your hubby find them. When he does tell him to remember how much you love him and place them in the jar. Remember to hide the hearts in lots of random places!
Not to mention "Father Christmas isn't real. Red bike when you were twelve?" What if he missed her so much already that he visited her through her timeline, just to keep tabs? Maybe even to figure out the best way for her to say "yes.