Ghost girl said “you have been coming here so many times” and we know that dungeon is not something you can do solo. So she has been risking her life many times to save him
Even if one says that she could have done much more, that doesn't invalidate what she has done and is trying to do for him.
It absolutely does invalidate it cuz she's only doing it for herself she doesn't genuinely believe he's alive she's just there to quench her guilt and feel like she tried
As an example imagine you watch your "friend" get beaten, stabbed and tossed in the ocean while you just do nothing and you never see him come back up then years later you come back to that same ocean to dive & search for him even if that ocean is filled with dangerous sharks do you believe you're doing it for him do you genuinely believe he'll be alive years later what do you think you'll find? do you even have the audacity to consider yourself his friend just for doing this?
That's basically what she did to him.
If she was threatened I'd at least understand she's a victim too but she was just like "they're not listening to me so that's rough for you buddy 🤷🏻♀️" she watched her "friend" get repeatedly beaten, stabbed and kicked into a river that flowed to the most dangerous floor while he was unconscious, had no fighting ability, food/water but cuz she feels guilty and comes back years later to look for what his bones? it's ok?
SUMMARY: She didn't do shi for him she just tried to make herself feel like she tried. She's just as guilty as the others. And I don't care if sum1 says "well you would do nothing too" it doesn't make it less terrible and do not project yourself onto me I would never do nothing especially not for someone supposed to be my friend.