when is enough a enough?

I think the point to stop is when it starts affecting your own peace of mind. Meaning, you can always be the generous one and even repay good for evil that is repaid for your kindness but at some point, especially if that someone else is family, for the sake of peace within the family and for your own sanity of mind it's better to leave that people alone at some point. Also, our perception of "trying to help" is filled with good intentions but since we might not really be helping the situation though we are trying to or meaning too, we might actually be making life more difficult for the other person without meaning or knowing it. So, yeah sometimes it's a bigger help not to help but just to listen and be there for a time when help is requested specifically. I think your trying to help someone regardless of their response, to an extent is good coming back to you. Alot of times, it should make you a happier and healthier person. I think alot of depressed people would do so much better if they put aside their woes momentarily and looked around to see what they can do to help out someone else, however small.