Unfortunately, Majasa’s mind was too far gone and you had to end her life. Even if she had a shred of sanity left, the injuries she inflicted upon herself in battle would have been far too much to ever recover from.
Thankfully the Lance of Heorot absorbed her power from her blood which seems to have worked in place of her blessing.
While you may have gotten what you came for, Apophis must be stopped, and you’re currently the only one here and capable of doing so. Find her and stop her.