It does pass, but in a way it's a grieving process.
We all know as parents that our children will leave home, but it can still be a really hard time.
My youngest daughter is the only one at home, she is nineteen, and we are very close, i am dreading her moving out, as I know she will.
We just have to go through the process, and make a fuss of our young ones when we see them, while never ever letting them see that we hurt.
I remember hearing someone tell me when I was little that the moment you start caring about anything or anyone, there is pain at the end of it.
That is true, but never a reason not to care and love.
Enjoy your daughter's company when she comes home, and know that this feeling of loss will disappear by degrees until you don't feel it anymore, and you appreciate your daughter for the independent woman she has become.