It is difficult to say precisely what type of coils Shirley Abbott intended to the reader to picture, she may have envisaged coils of rope, coils of barbed wire or even the coils of a serpent. However, not withstanding that we can extrapolate the meaning from the sentence itself.
She says that they are 'caught in the coils' so she is expressing that their freedom to indulge these unmatronly desires are constrained by metaphorical coils of their commonplace lives and circumstances. They can't travel, they have husbands to care for, they can't wear silks because they have houses to keep, housework to do. It is all a little ordinary, even if they are happy, so they dream of more glamorous lives.