It's not really bullshit to want something but wrestle with the ethics of it, or to balance different options. Like I said, she probably would have went with a repurposed stone or none if we exhausted other options.
Moissonite for her was this thing she had never heard of, something that didn't have meaning outside of a substitute for something else. It was untested. Heck, my guess is if she lost her stone she'd probably be fine getting a moissonite stone as a replacement now just because it's been settling in her head for years and years now.
In the end this is just me inferring how she feels. From my standpoint, I just wanted to do what she'd be satisfied with... which is another angle on the issue.
Just to add later: she did like the color and brilliance of moissonite. I remember her worrying about the hardness and not having an intuitive sense of how durable it was. I think if someone had been able to say "this has the same hardness as diamond" scientifically speaking she would have been ok? I have no idea. It was a strange gem to her and she was just as skeptical of it as she was about claims of any given diamond's provenance, ethics wise.
It's fascinating to hear how people react to that over the years, mainly along the lines of "I wish I'd been that brave". So there's definitely a social pressure to conform.