To be frank; yes - Cynthia caught him with Yoko whilst Cynthia and John were still married.
John later admitted to many affairs whilst married to Cynthia. Poor Cynthia came home from a holiday in Greece to find John and Yoko in bathrobes (Yoko wearing Cynthia's bathrobe) facing each other sitting on the floor. Cynthia left that night.
Cynthia was understandably shocked and saddened.
Cynthia Lennon.
John Charles Julian Lennon. On April 8th 1963 he was born to Cynthia and John Lennon.
Cynthia and John Lennon's son Jullian Lennon was born in 1962.
In 1968 he divorced Cynthia.
Cynthia Powell
both
John Lennon, who was married to Cynthia Lennon in 1962.
Cynthia died from cancer in 2015.
Cynthia Powell Lennon remarried, first to Roberto Bassanini, then to John Twist. She and son Julian lived in Wales during the 1970s and 1980s. She wrote two memoirs of her years with John Lennon, A Twist of Lennon and John. She married longtime companion Noel Charles in the 2000s, and lived with hin in France.
Cyn actually hated John. She thought he was a disturbance and a class clown.
Yes, twice. Cynthia and Yoko.