Helping them means being there for them through the pain, rather then taking all of it on yourself. I would take a small percent of the pain, perhaps 10%, just to show the person that they are not alone, but to take anymore would be an insult while also being detrimental to myself. After all, it's their pain to experience. We all have our own pains, and in the end we are stronger for it, even if at the time, all we want is for the pain to go away. Who would I be to take away that experience? Who am I to cheapen that experience, out of my own misplaced sense of chivalry?
err... tl;dr: none, or just a little bit.