Having been used to an empty house every other week (as a single mom/shared custody)- I've had practice at empty/quiet nest. This year, I started a twice a month Sunday dinner evening with two other moms (and dads of course) called "launching our last". Due to having a son that goes back and forth to his dads, I felt this would be a great way to build community (with his peers) and mine and also provide a lasting tradition on Sunday evenings. We've added others to the evening on an ad hoc basis. Of course since December, the talk often focused on the application process, procrastination, angst of waiting, surprise, decisions..and taking a "gap year".
The best part is that sense of pattern, to Sunday dinners coming up, and looking forward to a full(er) home than just the two of us, and of course a variety of cooks in the kitchen. I can see establishing new patterns, reaching out to treasured friends before the nest is really empty helps in transition.
Try it - you like it.