DEAR HARRIETTE: My son is going to leave for college in a week, after he spent a gap year living at home, working and learning how to code. He’s my only son, and having him out of the house will be a huge change for me and my husband. How would you adjust to having your child away from your home for the first time? — Empty Nester DEAR EMPTY NESTER: Our job as parents is to prepare our children to …