Sing to her, hug her affectionately, look deep into her eyes and passionately tell her the flame that is within your heart for her shines brightly, never flickering. Tell her that your breath and the very energy you find in the morning to move and live is hers and that, without her Love, you are nothing more then an empty shell, void of any feeling. Without her, you are incomplete.
Or put on a black wig and make-up, pretending to be someone else. Flirt with her and, if she takes the bait, you can hold it over her head that she cheated on you with yourself. :D!