But that makes more sense? Arthas stabbed her, pulled her spirit as a banshee to roam for days as her corpse was left to rot. Only days later when he was weakened she was able to get free and return to her body.
Then she fell from Icecrown and got herself stabbed, we don't know how much time actually passed when she was actually dead before Val'Kyr raised her back. And then She had headshot from Godfrey.
Her regenerating from that is just silly.