Why is Heather in danger of losing her standing with the marthas

Heather once again comes to Melinda’s door begging for help. She whines about the Marthas and says that they take advantage of her and do not appreciate her. She says the Martha's just make her do more work and do not acknowledge her input. They have asked her to decorate the Holiday Inn ballroom for prom, and she only has a few hours to do it.