Well, yes, those types of magicks do exist, but I wouldn't say it's more common for adventurers to come back from the dead than it is for them to not come back at all. Living as an adventurer probably isn't too much different than it is living as a jujutsu sorcerer.

There are things out there that can banish you to planes unknown with a thought, that can drag you into the deepest pits of the nine hells while you're still alive, or erase the memories of your existence from the minds of everyone you've ever known. Hells, there's things out there that can just look at you and tell you to die and you would simply do it, if they were powerful enough.

All this to say that Mina deals with people who share your lifestyle on a daily basis. She opens her inn and her heart to them, and welcomes them with warmth and compassion because she can't ever give anything less than her all, and sometimes they leave and simply don't ever come back. Or worse, their companions come back without them, and she has to see the looks on their faces, hear their tales, watch them mourn, and try not to burst into tears while manning the counter. She carries those moments with her, always.

So I don't think she doesn't understand what kind of dangers you face. I think she understands too well, and it scares her to see that you don't seem to care whether you live or die. She cares about you.

You have to prepare yourself for the worst, I get that, but if you can't promise to fight, to care, then every time she sees you, she's going to see a ticking clock. One more person she'll invite into her life who won't come back.