Katherine has taken her coworker up on his offer, and she's going on a date with him. Except, she's taking him to the toasting ceremony where her ex is. Gary gave her his approval and wants her to be happy, hopefully, her other friends will want the same for her.
It's a toasting ceremony in honor of Delilah and Regina's new restaurant, and everyone is invited to the occasion. By everyone, we mean everyone, including Katherine who is at an event with her estranged husband, his former mistress, and her new date.
Maggie: Maybe he just lost sight of the horizon. I was watching this documentary on JFK Jr. You remember when his plane went down? ... Anyway, Kennedy was a novice pilot. He was flying at night, and the clouds came in, and his instruments were telling him which way was up, but he didn't trust them. The truth was right in front of him, and he couldn't see it. He lost sight of the horizon and nosedived, and by the time he realized what was happening, it was too late, and he couldn't pull up. Gary: What does this have to do-- Maggie: That's depression. Now maybe he wasn't depressed; maybe something else was going on. People keep secrets from loved ones, and sometimes, you don't even know they have these secrets until an event like this happens.