What he meant was that being invulnerable could mean enduring through pain, surviving the unspeakable and not letting those who have caused you such pain hurt you when they're no longer there. In that respect, she definitely had the strength to become what she wanted most, without shutting herself off completely.

Unfortunately, it didn't come out that way.

She likely needed some time alone, regardless, to process everything that just happened.

"Take care." he called out.