Emily is the ex-wife to Cal the romantic comedy Crazy Stupid Love.
Emily and Cal first met when they were 15. They dated for 2 years before having their first child and getting married shortly afterwards. By the time they were 44, the romance had gone and Emily cheated on Cal. She confessed and then divorced Cal, kicking him out of the house and taking all their mutual friends for herself. It's little wonder why Cal would start having one-night stands after that. One woman he had recently slept with turns out to be their son's teacher. When she sees Cal and Emily together she assumes that they were still together when she slept with him and makes a scene. Cal and Emily avoid each other after that.
One night while Cal was searching for something in their front yard, he decided to call Emily, who he could see through the window. Cal noticed that Emily still lit up whenever she heard his voice, making him feel that maybe the relationship could be saved after all.
Cal and their children all collaborate on a way to get Emily back. Cal sets up a spot in their front yard so that they can renew their wedding vows, only to be distracted by his daughter Hannah bringing home a man Cal knew to be a womanizer. At that moment, the misdirected parents of their love-struck babysitter and Emily's boyfriend show up and a four-way fight breaks out.
At their son's end-of-year speech, they see how their negativity has jaded him. Cal decides to step up and say the speech he feels his son should have made, making a thinly-veiled love confession to Emily. Afterwards, Emily and Cal manage to patch things up and it's implied that they'd eventually get back together.
While Emily and Cal had the idyllic family life, she felt that Cal had lost his sense of adventure and that their lives were passing by. Emily's cheating on Cal was a badly-thought out plan to shake things up. Although she had tried to move on, her still-latent feelings for Cal reared up when she found out he had slept with their son's teacher, chewing him out in a jealous rage.
Many viewers have criticized Emily and Cal's relationship as an example of the Unfair Sex, as Emily is treated with sympathy by their friends while Cal has to earn his place back into their good graces. Even Cal thinks it's entirely his fault.
David was the man Emily slept with before divorcing Cal. Their relationship isn't given much depth, but apart from the infidelity, David does seem like a decent person. When he shows up at Emily's place with both Cal and Jacob present, Jacob punches him out as a sign of his loyalty to Cal. It's never mentioned if Emily stays with David after that.