He hoped that Abby would stop going to Owen, maybe he was afraid she would abandon him, or maybe he didn't want Owen to be like him.
He said he was old and tired, he wanted to be caught, so he became dull, but he chose to self-mutilate at the moment of being caught, and chose to "dedicate himself" at the moment of dying Abby, as this is the last drop of blood he found for Abby.
He is Abby's first "father", which may not even be known to him, but he knows that since he chose to love her, he has to give everything for him, including his life.
He knew that Abby would still have many "dads", and he didn't expect to be her only one, but she would be his only one.
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