Against every doubt and warning in her mind, she felt nothing but a joyous confidence; inexplicably, she felt as if his figure in that crowd was a point of indestructible security.
Matter is indestructible, it changes its forms, but it cannot cease to exist.
No matter what he had done to wreck his life, this was still the Francisco d’Anconia in whose bed she had been so proud of belonging-no matter what betrayals she had met from the world, her vision of life had been true and some indestructible part of it had remained within him-and in answer to it, her body responded to his, her arms and mouth held him, confessing her desire, confessing an acknowledgment she had always given him and always would.
There are no more uses of "indestructible" in the book.
Show samples from other sources
When the fear takes over, use the only thing more powerful, more indestructible, to fight it: your spirit.
Sabaa Tahir -- An Ember in the Ashes
"Nick, don’t let one good turn make you feel indestructible," Go said.