Unpopular opinion: Daenerys didn’t just “go mad.” She was betrayed, manipulated and lost almost everyone she loved.
She lost Missandei, Jorah and Rhaegal. Jon rejected her, Varys betrayed her, and the North never truly accepted her despite everything she did for them.
After 8 seasons of showing mercy, trying to do what was right and wanting to be loved and trusted, she finally broke.
That wasn’t simply madness. It was her breaking point.