No you recognize the reasons behind the jealousy and deal with them so that you don't react negatively the next time. It's not a trick of the mind it's a deep understanding of your own fears and drives. It's about trusting your partner means it when they say they love you. If you trust that then who they are with becomes a non-issue because love is not a sum loss commodity. The more it gets shared out the more there is of it.
She likes to have trysts with others but LOVES to come home to him. He is happy and content to have her happy and secure enough to meet this need of hers. She allows him to meet his own needs and they can live happily in the understanding that each of them is where they truly want to be.
It's a trick of the heart not the mind.