I'm a 41-year-old stay-at-home mom. My husband, Paul, is 48 and works in finance. We have two beautiful children: our 18-year-old son, Eric, and 15-year-old daughter, Mary. Our marriage had grown stale, but I never imagined it was this rotten. Last week, my life was annihilated. As my husband swiped up to close his phone apps, my eyes caught a glimpse of a text thread between him and Amy, our son's girlfriend of four years. I only saw a blur of words, but one phrase from her seared itself into m