Well, but what of suffering that has no direct causes? For example, most of my suffering (at least, that which is not self-inflicted) is not because of any specific person's actions, but because of the collective decisions that humankind has made over generations, poisoning the air and the earth beyond my body's ability to cope. It is hard to assign blame to such things! And, presumably, I too have played my own part in it.

Perhaps this is why I tend to consider suffering strictly internally rather than interpersonally. I may not like it, but it is good for me to suffer, since it turns my attentions to better things...