Enjoy this time. Take lots of pictures and put the dates and names and places on them. Give him all the love you have and don't obsess over the little things he does wrong. Make sure you give him direction and reason to want to love you back. Don't try to be his best friend, you are the most special person in the world to him, his mother.
Trust me, in a very few days you will be using his empty room to quilt in, and wondering when he will bring his wife and kids to see you.