I think it's good for you to want to help your friend, but when will your friend help himself? I'm not saying to leave him out on the streets, but even if his grandfather dies what does this guarantee? You both have to move on and how long can he survive, if you don't? You might be the only helping from the bottom of your heart, but he has to want help to be helped, not take advantage of his friend who puts his wellbeing on the line for him. I say to think about a future with or without him and weigh them both, what are the pros and cons and are they worth it in the long run?