W.W.J.D.?

I have a fantastic wife who is very good at holding me accountable. Tonight as we discussed my sister-in-laws financial woes, she looked at me with tears in her eyes and asked that dreaded question, What would Jesus do? I say that dreaded question because that is when I have to put aside all my personal thoughts on how someone else should do something and look Christ in the eye honestly addressing the issue at hand. This question is do we help someone Financially who spends foolishly, taking her car payment to get her hair done, or do we give her as sound advice as we might have? She usually rejects verbal help saying we are "not understanding" or butting into her business. Now I face that question, what would Jesus do, with little or no clue as to what He actually would do. How do I remove my personal feelings and actually try to think as He would? Would He enable her Foolishness or would He be compassionate to her need? I feel I know the answer but I also struggle with "what you did for the least of them".
Praying for the answer,
John