Obviously because he can't have her. Why else are men so obsessed with women in their past?
She will never be his. He cannot tolerate that reality and so he will keep her alive by obsessively speaking her name wherever he is at rallies and luncheons and state dinners and in bed and on the phone and when with others and when alone. She is part of him. He has no pride where she is concerned. He will speak her name forever because that is as close to her as he will ever get. He is enamored ensnared entangled.
A stalker for sure. A threatener for sure. A disparager for sure. Anything to get her attention so she will notice him and pay attention to him and speak to him and meet with him and hopefully one day succumb to his protestations of abject love and devotion and surrender unto him. Nothing so sad as an old man carrying a torch for a woman he will never have.