A little late on the answer, but basically she was deceived by the dragon who crafted the armor, it was cursed and corrupted her entirely. A twin set of armor suits were made for her and her husband, with the point of enhancing their abilities to the point of absurdity, but they were both designed to trap the ponies in an eternal struggle, so as to disable the most powerful fliers in the Equestrian Air Force. Even after their death, Blackmane and the Sky Titan's souls were trapped in their armor suits so that they can continue fighting each other long after the war was over. That bird looking thing you see in the background is actually a Sky Titan, a literal manifestation of all pegasi weather magic and the actual atmosphere itself. When she summoned it, it generated such fierce storms and lightning that it took out the entirety of Canterlot, two griffon airship fleets, the entire pony Air Force and Blackmane and the Sky Titan themselves.