It's Complicated (2009) (R)

synopsis

Jane is the mother of three grown kids, owns a thriving Santa Barbara bakery/restaurant and has -- after a decade of divorce -- an amicable relationship with her ex-husband, attorney Jake. But when Jane and Jake find themselves out of town for their son's college graduation, things start to get complicated. An innocent meal together turns into the unimaginable -- an affair. With Jake remarried to the much younger Agness, Jane is now, of all things, the other woman.