In what manner is she pursing that? You asked later in the post if you should go to court over it or just pay her. She would need to legally pursue this through a court. There is nothing automatic about I-864 enforcement. Presumably it was brought up during divorce proceedings, but possibly not. Using the I-864 for spousal support after divorce is a legitimate thing, but enforcement (or not), length of enforcement, and dollar amount of support (if any) will vary greatly depending on marriage length, ability of spouse for self-support, difference in pre- and post-marriage income, and (probably most import) WHERE the case is tried. This is definitely a divorce lawyer situation, but you also need somebody that has plenty of experience with the I-864 also.