Let's be honest folks. It is unlikely that any of us know to what limit we would go to save someone else.
There are examples of people going into the most extreme conditions to save others only to die, and these were people who knew better.
Would I go to any depth to save someone? Maybe. Maybe I'd be willing to die trying. I do not know for certain until it happens, and even then I do not know until I say "Enough, this is as far as I will go." We can talk about it, and mentally prepare for it, but the proof, as they say, is in the pudding.