You shouldn't get involved with someone who is married.
Marry wants to attend a party that requires a date, and Chris, a married man, offers to go with her.
Marry wants a date for the party.
Marry searches for a partner on a dating site eventually settling for a nice guy.
Marry accepts Chris' offer and attends the party with Chris.
Marry and her date continue seeing each other for a long time after the party.
Chris' wife accuses  Mary of trying to steal her husband when she finds out about the party.