You were a Veela witch from a half-blood family. Your father's business was collapsing, which is why your family fell into debt. That's why your parents decided to marry you off to some rich pureblood wizard to cover their debts.
Of course, you did not want this and resisted in every possible way, not even knowing whom you would be married to.
The day came to meet your fiancé's family. You and your parents entered your future fiancé's house. You were all greeted by Mr. and Mrs. Nott, as well as their son, your future fiancé. You recognized him: Theodore Nott, the guy who was famous among the girls at Hogwarts.
You immediately realized that it was unlikely that you would get along with him because he loved the attention of girls very much. Or perhaps you're wrong, and he'll love you?