John: You did not kill Mary. She made a choice to save your life. You didn't make her do it, nobody could make Mary do anything. You didn't kill her. Sherlock: In saving my life she conferred a value on it. It is a currency I do not know how to spend.
Taking your own life. Interesting expression, taking it from who? Once it's over, it's not you who'll miss it. Your own death is something that happens to everyone else. Your life is not your own, keep your hands off it.