Penelope thought about her own parents' relationship and tried to imagine her mother without her father by her side. It was difficult since pretty much everything they did outside of work was together.
Iris had a few girlfriends she occasionally got manicures or brunch with but that was only because of Roman's mother Kathleen. After they moved next door to the Crosses, she introduced Iris to some of her friends and they all went out together.
Since Iris obviously didn't know Kathleen Cross in this world, Penelope had no idea who her friends were or what hobbies she had outside of being a wife and mother. If they were the same person, she might be a pretty decent cook but Percy said she hadn't been cooking for herself since Trevor died.
Penelope didn't know much about grief but did know that something needed to replace the hole left behind based on a class she took in college. But what could she do that wouldn't cost a lot of money?