Wasn’t Daenerys married at one time to her brother?
It seems like the nobles houses of that universe do the ancient Egyptian royal thing. I guess normal genetics don’t work there. (Why would it they have Snow Zombies!) So sleeping with her nephew? I can’t see how this would upset her that much. I think its the competition to the chair more then anything else.
No, her brother Viserys gave her in marriage to Khal Drogo. Viserys' hope was that Khal Drogo's army would help him regain the throne. Viserys did not even survive the first season.
Not that I know of... If Incest wasn’t a big deal, Cersi and Jamie wouldn’t have been willing to toss Brant so casually from the tower just to keep their secret....
Incest is not something that the GOT Universe has ever embraced as acceptable, even though its been part of the story almost from the start.
The fact she found out her lover was her nephew didn’t even seem to register, simply the fact he could be a competitor for the throne...
No, but since Targaryens routinely married each other, she said in the book that she had just assumed she'd marry her brother and was taken by surprise when he traded her to the Dothraki in exchange for any army.