You never MEAN to hurt her.
There's one thing I'm black and white about in relationships: if you cheat on someone, then you didn't really love them. I know. You think you loved someone and you just made a mistake, right? But if you actually care about her, stop messing with her head.
You think you're doing the right thing by telling her you'll never do it again, by asking for her forgiveness. Or you think you're doing the right thing by never mentioning it, simply trying to change your ways behind her back, hoping she'll never know what you did.
You don't want to hurt her, so you try and convince yourself that you love her, that you're happy with her, and that you want to be with her. You go back and forth, continuing to screw up, asking for forgiveness again, vowing you'll get it right this time.
You tell her things like, "But I can't imagine my life without you," because it's true. You can't. But that doesn't mean you can fall in love with her. It doesn't mean you two are meant to be.
It means you're worried about your own conscience. It means you think you can make yourself love her so you won't feel guilty and so you don't have to hurt her. But all you're doing is messing with her head and causing her more hurt and anguish.
It's like putting a band-aid on over and over again, ripping it a little bit, then slapping it back on tighter. The next time you pull it, it hurts worse, so you quickly push it back down again. Over and over until she's numb.
You didn't mean to hurt her. You didn't mean to fall out of love with her. You didn't mean to think about what else is out there.
But you did.
You did all of those things. And giving her false promises or hoping you can change only hurts her worse. You can care about someone without loving them, you know. You can worry about their well-being and their life and their heart without wanting to be with them.
If you care about her, think about her. And then stop messing with her head. Because all you're doing at this point is saving your own ass. And that's not how relationships work.