sorry hon. best you can do is help your DS keep his expectations LOW. not talking up daddy time, not even talking up daddy.
it is tragic that a man who works on his OWN schedule is unable or unwilling to MAKE time for his child. it says a lot. his priorities are messed up. and there is not a thing you can do to CHANGE that.
i hope you and the boy do some fun things today! silly things. goofy things.