How long is long enough to start dating again?

Oscar Mikols/Pexels

They dated for about 2 years. (I will call them Man A and Lady B) Me and all of their other friends saw them as a happy couple. They vacationed, celebrated birthdays and 2 Christmases together… And as per their pictures, they had ravioli together, drank several glasses of fruity vodkas mostly on weekends and attended to a few basketball games… She also met his parents! They seemed like one of…