I wan't to move but am already homesick before I have even left. I know this is a necessary move but.....?

I am 42 years old and have been having trouble with my son for years. I have tried everything to make our relationship work. I have gone to the Dr. to get medicine for depression and severe anxiety and stress and have gone to counciling to learn ways to better deal with our situation. I married a man 23 years older than me 10 years ago, who gave up everything he had planned for his life because he loved all of us. My son and him have had problems from the beginning. My son has hit him, verbally abused him and given him absolutely no respect. All the while this man has been everything a dad should be. My daughter and him have had problems but are now the best of friends, he's her dad. My kids have both moved out, and I am on my way to Florida, I can't wait to start this new chapter in my life, but how do I do it without missing my parents, of which my dad has had cancer, and my daughter. I haven't even left yet and I am feeling lost and homesick. I never knew it world hurt this bad!!