Dear Married Asshole,
What part of "leave me alone" do you not get?!? Do I need to say it in a different language? Do you need a remedial class on what "leave me alone" means and all the context?
And we were never friends; so stop claiming we were. You were and always will be the biggest mistake I made in my twenties and I wish I never met you.
Stop saying you want me and that you'll leave your wife for me. You have never shown any other interest other than wanting to feel me up in the middle of lecture and to get in my pants. I'm sick of your lies and you, in general.
I would tell her everything, but you're such a good liar. I bet she even believes you when you tell her you love her, but then you told me the same thing repeatedly.
So please, for God sakes, leave me the fuck alone or I'm telling her. She really deserves to know how much of an asshole you really are.