I agree with Karen.Just try to enjoy the time that you do have with him.There is really no true way to make it any easier except to do exactly what Karen said to do: Take life one day at a time and live in the moment.That's the best advice anyone can give.I wish you luck and the best of everything.
Keep us updated and keep posting when you go away to college.We want to know you do and how the college life is treating you.