I'm curious too (≧∀≦)
The stigma is probably what sent her back it time, and if she doesn't try to change then their god would personally interfere. OR he'd chosen her BEFORE she returned back in time, but she didn't go the right path the FIRST time, so he's already had his interference by just giving her the stigma.
Spoiler by user GG-IS-BAE
Jermel, the commander of Black Knights, would meet the same death as did Judith in her first life.
√ After his death Judith would became the the commander of Black Knights.
√ Judith and Giryu (ML aka the commander of Red Knights) will get married.
√ Judith will be pregnant with baby-boy.
√ Judith will be able to meet her swordsmanship teacher from her first life.
√ The first Princess of Empire Olga will become emperor, the ruler of the country, and later she will became the saint.
√ Princess Olga will be married to the White Knight (it seems he is the commander of the White Knights).
Spoiler by user sheeeeeeela
Spoilers please