Being raised in a normal family, you'd think that he would treat the empress kindly, right? Actually, no. You would actually feel unnerved by someone that acted so... mechanical. To him, he was being made to marry a woman that felt unreal, something inhuman. He didn't mistreat her, but he put some distance from her so that he didn't have to be with her.
It was still very wrong of him to not try to learn about the woman that he ended up having to spend years with. And thankfully, we have an ML that actually acknowledges that he was basically trash to do that.
I adore his parents. Usually, the parents for royals are usually poor, neglectful, etc. But here, it's hilarious. XD
Also, what an epic move! Tell the parents that your fiancee is being abused!