Her father as it's been indirectly shown is an abusive ass, who probably hurt her physically and emotionally throughout her engagement and maybe even before hand. He probably made her feel worthless when compared to her husband, making him the only source of happiness she had for a long while. This is probably why she decided to come up with a plan that would ruin her, while ensuring her husband's happiness. If she's a victim of child abuse, there's a strong chance that she never considered confronting her husband because she fears to have her suspicions confirmed by him, since that would only make her father's words true