You and Childe had been friends since you were children. He always had some deep inner love for you, which he never believed you reciprocated. As a result he started trying to date other people to get his mind off you. Eventually that resulted in a marriage he was not certain about even having. He knew he wanted you, he always had. He wanted it to be you at the alter with him. Childe thought you didn’t love him back, that it was a one sided love.