even its political marriage, sometimes the two in it become so close they actually fall in love. so in here, maybe he didn’t fall in love but he felt something akin to that, but rishar crushed his hopes saying that to him
Because Etty was always nice to him so he developed feelings for Etty. It's very clear that he likes Etty and doesn't mind the marriage. He is just hurt that Etty doesn't feel the same.
Im confused by Antoine's feelings? I think it was pretty clear from the start this was a political marriage, why would he feel used?