I cheated. I can't live with it.

I don't even know where to start. My heart feels like it's going to explode. It's been eating me alive for months, and I can't keep it in anymore. I cheated on my boyfriend, Mark. We've been together for five years, since college. He's... he's the best person I know. Kind, funny, supportive, everything you could want. And I threw it all away for one stupid night.

It was a work conference. I was feeling insecure because I was surrounded by all these successful, polished people. Mark couldn't come because he had a huge project at work. I felt alone. I drank too much at the hotel bar, and then I met this guy, David. He was charming and said all the right things, made me feel like I was the only woman in the room. I knew it was wrong, even then, but I let it happen. We went back to his room. I don't even remember all of it, just flashes. Disgusting.

The next morning, I felt like the scum of the earth. I wanted to die. I haven't told Mark. I can't. I'm so afraid of losing him. He trusts me completely. He tells me everything. We talk about our future, about getting married, having kids. How can I look him in the eye knowing what I did?

I've tried to convince myself it was just a mistake, a drunken lapse in judgment, that it didn't mean anything. But it DOES mean something. It means I'm capable of hurting the person I love most in the world. It means I'm not who he thinks I am. I've been distant lately. He's noticed. He keeps asking me what's wrong, if I'm okay. I just tell him I'm stressed about work. The guilt is suffocating me. I have nightmares about him finding out. About him hating me.

Sometimes, I think I should just tell him. Rip the band-aid off and face the consequences. But then I imagine his face, the hurt in his eyes, and I can't do it. I'm a coward. I don't deserve him. I don't deserve anything good in my life. I just wanted to get this off my chest, even if it's just to strangers on the internet. I don't know what to do. I really don't.