Joan’s husband, Seth, was having an affair. All the signs were there.
It was one of those situations in which she owned half the house, so wasn’t going to leave it, (and let Seth move Slutina in) and there were so many things happening, she couldn’t deal with adultery right now.
She had known Syl for years, they’d worked together, were members of a particular group. There never were any sexual connotations.
But with Seth out on many nights and Syl her friend, things moved in an unexpected direction.