they played around with that and how she treated Jon and Arya in Season one....she's been getting tutored in cruelty and manipulation by some of the best teachers one could have since then.... it only makes sense that the victimized become the victimizers

Danerys is destined to go crazy.... the people around her make her halfway good.... I think ultimately it's gonna be 4 main factions in the end... The Starks and whomever's following them, Dany and whomever is following her, MAYBE there will be some Lannisters other than Tyrion and Tommen left, And then there's the White Walkers.....all this with Bran bein the fifth faction to help them save the world, which they'll fail at...