What is the worse thing your boyfriend/husband/lover has done to you?

I'm writing a story on relationships and I want to know...what is the worse thing your mate has ever done? I'll share ONE of my worse with you...my ex slept with my so-called best friend in our bed, right next to me, while I was passed out drunk. Please be aware that I am submitting this piece to several magazine editors, so your comments will NOT be credited. You will have total anonymity, so help me out and spill the beans!