Being able to influence the outcome, being able to do something about it, to be able to stop the bleeding. You're not being useful if you're just standing there going "Oh, that's awful!" You're only useful if you actually do something about it and I think that goes for everything. If you actually do something about what's in front of you, then you are actually contributing and you haven't got time to be self-centred or sorry for yourself. You should be doing something about the person you really should feel sorry for.
