Pretending. He used to do it when he was younger. He'd pretend that he was a Marshal like his dad. Like his grandfather was. He liked it. Running around the house with a plastic gun. Barging into rooms and startling his mother in the process. He liked to pretend.
When the ring got stuck on his finger at the diner, he had to pretend that it was accidental. Truthfully, he had subconsciously done it on purpose. It was Mary's ring. Her engagement ring. He liked having a part of her with him every moment, and the fact that it was a ring was like that it was a wedding ring. He was pretending that he was married to Mary. And truthfully, he loved it.
When Eleanor pulled it off of him, so quick and swift, he felt instantly saddened. The minute the ring left his finger, he was reminded that he was alone. That Mary was with someone else. That she wasn't with him. It was slightly depressing. He was in love with her and the only thing he had of hers, his wedding ring, was taken away from him in the blink of an eye.
He'd have to pretend again. Pretend that everything was okay. Pretend that he was happy that Mary was engaged to Raph. He'd have to pretend, once again.