When you love someone, that love has no limit, no measure, because you know in your deepest being that when that love demands sacrifice, you will give it without question. You will not look for reasons, for justification - the act of giving, of sacrificing, is a natural compulsion, like breathing, and it will, in the end, surprise you because you did it without second thoughts.
Robert DeNiro, who may be the greatest living actor, usually acts in a way which is very stone-faced, like Steve McQueen. For example, Steve McQueen, if you cut the sound, you don't know what he's acting really. He gives to the lines, to the text, something very special, and he's very good. He was a great actor. But, to do a silent movie, you have to have more expressive actors.