If you read about Rand's philosophy, it is not a sacrifice to do something for the loved ones for free. Their happiness is your happiness, so it's in your interest to make them happy.
My mother never asked me to pay her back. I payback to foreigners and friends for their services. I don't ask people to do something for me free, nor do something to others for free.
If you would read what she was writing, she said, that it is in her self-interest to do this. If you can't leave without this person, than it's okay to risk your life for him. It is in your self-interest to do it, in other way, you will not be living