Bobby was sitting in his car thinking that his wife has run away with their daughter. The letter that was written in Scarlett's handwriting said that she is not happy with him and she is not feeling safe with him. Their relationship was pretty shaky already, at least according to him, after his accident and his mother's death. He didn't want to get home and was hell bent on finding his mother's murderer although he never showed his true feelings to anyone.
He did receive some compromising pictures of his wife with another man and he found out that it was Harold Harrison doing it. It was sometime before last year, before the attack on Jerlina. He didn't tell anyone about it and handled it in his own way. He met Harold in an alleyway and talked with his fists so that it would register in his brain squarely.