I think you can send him a letter, a really nice one if you're nervous... or ask him out for lunch, dinner, whenever he has time and talk to him. Explain and tell him, I am sure he will understand...
good luck
I have grown up with my uncle my whole life, and we are very close. Now he is married and moved out.I would like to live with him because of family problems. He used to offer for me to, but now he hesitates to answer. I love him so much! How do I ask?