Heh, that's actually a bit funny, because her own thought processes at the moment are desperately unfit for a leader. She's not being brave--just unhinged.
She watched a friend get murdered and had to stifle her raging desire for revenge. She fought in a battle she felt we likely wouldn't survive, in the name of her friend's killer. She lost her mind briefly when she saw a demon prince rise. Now another friend is running toward his death. And this has all just been the past hour...
I think the only thought in her mind right now, running on repeat, is "enough." Girl has had enough. Mama bear ain't losing another member of the tribe right now. If that means her own death, she just doesn't care at all. Enough.