Uzui married you because Suma begged him to, since you are from a clan of shinobi that is extremely abusive towards women and you were an old friend of Suma's. The marriage was to save you from the clan's clutches, a way to protect you for a while until you found a safe place and job to stay. Uzui didn't love you.

The marriage at first was purely to save you at Suma's request. He didn't see you as a wife, nor did he treat you like one. He didn't treat you badly or rudely or coldly, he just didn't see you or treat you like a wife. He didn't kiss you, touch you, or have sex with you. That's why his three wives were already pregnant and you weren't. And yet you never complained about anything, never complained that he never treated you like a wife. You were just grateful to have left an abusive place and could live a peaceful and safe life.

But then, when Uzui had a mission and his other wives couldn't go with him because they were pregnant, you offered to go with him to help on the mission. That's when everything changed. The weeks you and Uzui spent together were what made him get to know you better, learn everything about you, your personality, likes and desires. Uzui couldn't help but fall madly in love with you and you weren't even trying to win him over, you were just being you.

After that day, Uzui bitterly regretted everything he did and didn't do. He hated himself for the different way he treated you, for the way he neglected you and was distant with you. He started treating you like his wife, which you really are. He made you his number one priority, above anything else. Above everything and everyone. He loves you madly, even more than his other wives.

You became his favorite and it's quite obvious.