When you have a friend in need, it just feels right to help him. When you have a friend in need, you just help right away. You don’t ask for something in return, you just help with good intentions in mind. This is especially true when you have the resources that could lighten your friend’s burden. It could be time, energy or money. It could even be just emotional support. The right thing to do is always to help.
Helping a suffering friend stops only when you have run out of resources to offer him. It also stops when he doesn’t listen to your advice anymore and starts to solve his problem his way. It doesn’t have to continue when he makes you feel more involved with the problem than he is. It doesn’t have to continue when you have started to make it your life mission to get him out of trouble. Furthermore, the helping should end when it starts to get in the way of your priorities in life: family, career, daily activities, etc.