What would you make of this?
Husband takes the dog on an uncharacteristically early walk without waking wife. Soon after, wife wakes and decides to run to the park thinking that she might meet them on their return. Wife meets husband and dog on their return stretch of the park. On turning around to join husband on the return journey, wife sees a couple in the far distance, exiting the area. The woman of the couple is a woman who the wife has previously suspected her husband of having an affair with. The man of the couple is this OW's husband. While walking away, OW looks around once directly at husband, dog, and wife, turns her head back, then immediately turns to look again and holds the stare for a few seconds. OW's husband is walking alongside her but does not look back.
Wife continues her conversation with husband, pretending not to have seen the other couple.