ok, it's cute, but you're feeding into it by fawning all over him when he acts like this. You're the humans - you can come and go as you please without any apology or worrying about the dog. You need to act like nothing at all has happened when someone leaves. Let him whine or whatever - just ignore him when he acts like that. When he starts acting normally, then you can play with him and have fun with him or give him a treat or whatever.