In your dad's defence, he is not happy about not seeing you for 4 years, not about money for himself. You did say you think about him and will regret if anything happens to him. Well. if you really mean that and are worried sick about him, you really should try to go see him. Pardon my language, but not having enough money or time is not a good excuse, it is all in relative terms. Life is short. Never miind what your dad or other people think about you, the fact is that all this is between you and your conscience. Give him all the love you can find in your heart (and money when you do have more in the future), you will find parents (most parents anyways) are very reasonable.
Good luck and wish you and your family well.
Good luck and wish you and your family well.