The adventures the two had put a strain on his emotions, however. He became more and more frustrated by the stubbornness of his partner. This culminated in Robin resigning after he found out his girlfriend, Barbara, was Batgirl, and Batman had known for some time. Grayson left Gotham to travel the world on his own, much like Bruce Wayne did in the years before he became Batman. While living abroad, Dick studied many different crime fighting techniques and re-examined his feelings about taking up the role of Robin again when he returned to Gotham. He eventually realized he had outgrown the role of Batman's trusted kid sidekick Robin, and set about developing a new heroic identity all his own.