Yuna never intended on abandoning her journey to get married to Seymour. She considered marrying him to make the populace happy and then trotting off and completing her journey anyway.

Quote Originally Posted by THE SCRIPT
Yuna
"If my getting married would help Spira..."
"if it would make people happy..."
"If I could do that for people... maybe I should do what I can."
"I never imagined doing anything like this."
"But, I won't answer till I know what's right."

Tidus
"Seriously?"

Rikku
"You could always just quit your pilgrimage and get married."

Yuna
"I will...go on."
"I'm sure that Lord Seymour will understand."

Rikku
"Umm, I guess so..."

Yuna
"I am a summoner!"
"I must fight and defeat Sin."

Auron
"Like Braska before you."
I never understood why people disliked Yuna. I always found her devotion to self-sacrifice a good plot line to go in contrast to Tidus's self-serving plot. I always found that Tidus gets offed at the end and Yuna lives on to be a great irony.

Furthermore as for the kidnapping occurrences, there's an entire plotline in the game based around the Albhed nabbing the Summoner's (male or female) to stop them from sacrificing themselves on their pilgrimage. I'd understand punishing the writer's for including Yuna getting kidnapped a lot of it had nothing to do with a core part of the plot, except it does.