Reasons

She wasn't in love with him.

Every woman in the city most likely had their eyes on him. He was one of the most eligible bachelors in Republic City. He could have anyone he wanted.

He was older than her by half her age and they had nothing in common.

Well, even if she was interested in him that way, it would be alright back in the Water Tribe. She was a year ahead of the marrying age, and her great-grandparents had age gaps as big as theirs.

Besides that, they were in complete different worlds and ran with different social crowds.

She wasn't in love with him.

He was conceited and arrogant. He thought he could get away with anything he did. Anyone could get knocked out by how overconfident he was. How could anyone stand it?

Someone ought to show him his place, and once she had the guts to, she'd be the one to do it.

She wasn't in love with him.

He was good looking, - no beyond handsome. Even by Water Tribe standards. The shape of his face, carefully angled and sculpted.

At times, he may seem extreme, but he did care deeply about the city and the people.

At least for now… she wouldn't say she was in love.

Song inspiration: I Won't Say - from the film Disney's 'Hercules'