Yes, he had begun to lose his marbles before the scene was set, that’s not in question. What is important to note is he was a loving and caring family man with a good job. There was no backstory of psychotic behavior, such as causing harm to animals, beating on people or finding pleasure in harm. He had emotions and trouble resolving them due to the circumstances with his home and professional life. Everything else after that was the storyline of his fall from grace. “Falling down.”