Whatever those reasons are don't explain why he didn't dance with her considering what we know now of the implications. It doesn't matter that he doesn't like her, its politics. It doesn't matter that he doesn't trust her, if its that bad then he shouldn't have married her in the first place.
If he can't put his feelings aside in order to portray a united front with his queen then he shouldn't have married her.
Spoilers(sorry can’t really talk about without the spoilers don’t read it if u don’t want to):
He was raped by his first wife when he was just 15 yrs old he couldn’t touch any women after that’s why he didn’t dance with past Abigail, after he tells current FL why he couldn’t dance with her when they were practicing FL finally understood him so she doesn’t try to force him he still tries tho(this part is actually coming up soon it’s just a few more chapters)
I know the spoilers. None of that matters to me. In fact it makes it even more odd that he would get remarried.
But he did. So as King he needs to find a way to at least communicate with his Queen. And he should have done so before making her his wife, because based on the early chapters he didn't even mention to the original Abagail that he wouldn't touch her until after the wedding.
I can’t remember well but I think their marriage was just to get those people who kept forcing their kids to marry him to stop, that’s why he married Abigail(sorry it’s been a while since I read the novel so I can’t remember the full details) he wanted someone that wouldn’t try anything but then past Abigail started to have feelings for him and started trying to get his attention and all that
I wouldn't be surprised if he got married just to get the nobles off his back. But based on what we have here in the manga it seems that Abagail didn't know about his plans. And became obsessed once he told her that he would not touch her. It wasn't that she loved him, she just had too much pride.
I've been spoiled on what happened to real Abagail, but basically she was raised to think that something had to be wrong with the woman if the man didn't want sex. Which explains why she was so obsessed with making sure not even the female servants looked pretty. Also she apparently died after tieing her corset too tight, and then our Fl inhabits her body.
Wait seriously she died because of that now I feel like I missed something cause I thought she was poisoned or something wtf damn now I need to reread the manhwa and novel and yeah I think it was because of what u said about her becoming obsessed and all that I think I mixed up this story with another one

If he can't even pretend to be cordial to his queen in public then why have one? Who cares if you don't love her, at least dance in public, its politics!! And if you can't take politics then step down from the throne