She knew that Isaac had a very strong and powerful background. She also knew that he was one of a kind and that he was capable of doing anything he wanted to do. If he really wanted to drive her and her entire family out of Aurous Hill, he would definitely be able to do it.
That way, instead of being able to defend her own marriage, she would only be destroying and causing harm to her own natal family.
Her natal family did not have many abilities in the first place. Now, they could finally be