Found: Help! Mystery/Psychological thriller written between 2017- present or so

Fiction
Mystery/Psych thriller
Written by authors similar to Ruth Ware, B.A. Paris, Lisa Jewell, Shari Lapena, I believe

SPOILER about plot (if allowed):
Set in England- a middle age couple, female partner is well-to-do and comes from family money, male partner is recently laid off after an incident on public transport so began a new job at a coffee shop. Female partner recently hires a young woman and becomes friends with her and her male partner. The 2 men decide to buy a yearly water transport pass and commute to work together as they work near one another. The older male begins an affair with the younger female hired by his partner. The couple in the affair plot a plan to kill the younger woman's partner. SPOILER TWIST- the young woman sets up her older affair partner and he is sent to prison for her crime.

This is The Other Passenger.

>2 SJaneDoe: Thank you!!! This has been driving me crazy for days trying to figure it out!