I was with exDp for 4 years, 1 ds. He was EA throughout our relationship and treated me very badly. I left and he was happy about that. I started a new relationship a few months later with a lovely man, treats me brilliantly and I love him. But I had sex with my ex. He'd been trying to get me back for a few weeks and I caved. I have no idea why I done this, I immediately regretted it. It's not an excuse but I was drunk, he wasn't. Now exDp is threatening to tell new bf. New bf would def end things and I would be completely gutted. I really don't want to tell him. What do I do? I know I've been a complete bitch.