Hi Patti,
I'm also an empty-nester, though my son is entering his 3rd year of college. He spent his second summer at home, working, but we know he won't come home anymore except to visit. (Or to move back in with us after college as so many do!) I went through a brief period of depression in the beginning--how can you not? You raise them for 18 or so years and then off they go. It felt like a part of me was missing. Two years later, he is so happy at school, and I am happy for him and pleased with myself for helping him to become a great young adult.
You will get over the depression, but then you have to decide what to do in this, your next phase of life. You could go back to school, get a job, do community service, so many things. Have some confidence in yourself; you've got to be pretty sharp to raise two kids and send them off to college.
Best,
Marci