So her “logic” (and I’m stretching that word to the breaking point) is that God said he wouldn’t destroy the world again with a global flood. Let’s say we accept that as fact: God will not destroy the world via a global flood.
The problem is that God isn’t destroying the world, man is. And man isn’t destroying the world via a giant flood. He’s destroying it by changing the global climate to the point that he can’t keep up. (To be technical, man is destroying his ability to survive in the world, not the world itself. The Earth would be here even if we decided to burn more fossil fuels.)
So even if we accept Genesis 8 as a valid “argument” (more word stretching), it doesn’t apply. Now, if scientists start saying that a deity plans on instituting a global flood via 40 days and nights of rain, then I’ll accept Genesis 8 as a counter-argument.