Grace After Henry by Eithne Shortall (2019)
Grace is devastated when her partner Henry dies in a bicycle accident. She keeps thinking she sees him as she goes around Dublin, and her only solace is remembering their times together and visiting the cemetery where he's buried. One day she's stunned to discover that Henry had an identical twin brother, Andy, that he didn't know about (both men were adopted by different people). When Grace is with Andy, it feels as if Henry is still with her--but is having Andy in her life the best way to move forward and heal?