Have you been a bad girlfriend? It's all right, you can tell me. I promise I won't tell.
If you need to get something off your chest, you can tell me. Don't worry, you're not a bad person, you've just made a bad decision. It always helps when you can talk about lying. It's the first step to being honest to yourself and others. Just submit an anonymous post. You never know if someone is going through the same thing.