I think the woman feels insulted. For whatever reasons she and her partner have they chose not to get married. However since they are living as a married couple she feels that is how it should be recognized. To have her partner dance the humilation dance doesn't just humiliate him, the one doing the dancing, but in her mind it is also humilating her who will sit on the sidelines, pregnant, believing that she should be considered his wife although they didn't go through the pomp and circumstance of a wedding themselves (or even a quick city hall trip).

His family probably doesn't approve of a common law marriage and are now trying to emphasize the fact.