Empty Nest Syndrome: What have you found that helps?

My neighbor's youngest son just left for college. He is doing OK, but he says his wife is sad to come home to an "empty house". He jokes, saying, "what am I, chopped liver?!". But, we all know what she is going through: Empty Nest Syndrome.

I found an article on the EmpowHer site regarding Empty Nest Syndrome: https://www.empowher.com/encyclopedia/empty-nest-syndrome-how-cope-when-...

Is anyone else going through this? How are you handling it?