Well what I did might not work for you... it involved a backrub and adult personal affection

....After which my DH will agree to most anything...
How ever, it never hurts to do more then your share of laundry folding,moping the floor,change the sheets, backrub and foot rub... you know what she likes!
A good romantic dinner, with wine, during which you sigh and say some thing like" This almost reminds me of how wonderfull that dinner at(insert WDW rest. name here) was, and how wonderful and relaxed you look...."
Or with Valentines Day coming a box of Choclate, and a flower arangement with a Disney toy/floral pick and a card with a Voucher for a "Romantic" get away for 2 to WDW... Pre paid, non refundable!
And then for the 2 trip. Guilt. Have such a good time by your selfs that while you are there sigh ever once in a while and say how much you enjoy just the 2 of you, but is that fair? So you can then plan a "family" trip to ensure the entire family gets to bond.
Best of luck.
I usually just plan and tell DH we are going, he works so hard and such long hours he is happy just not to have to make a lot of decisions!