A Guy so obsessed with a girl but then she turns out to be nothing that he wants or so he thinks in that instance, so in a rage he kills her and dumps her body, then realizes what he's done and regrets it. When he repeats that he won't let this build up inside of him, that's his mind lying to him. He did let it build up and when he says she isn't real, I can't make her real that's when he comes to the realization of what he's done. he was so wrapped up in fantasy he lost his mind. That's my take anyway.
