I personally believe that if God doesn't want something in your life, it will continue to hurt you until you have absolutely no choice but to separate yourself from it. For most couples, cheating is that separation point.
Let me just start by saying that life goes on. You learn from the mistreatment, the world keeps spinning, and then, eventually, you honestly couldn't care less. So it will be okay! Also, if you wish bad on the person after they cheated, maybe you didn't feel the way you were supposed to originally feel as well... When you genuinely care about someone, you genuinely want the best for them at all costs, and that should not completely change overnight. If they want to talk bad, let them. If your ex talks bad about you when you've done nothing wrong, it's most likely because they're channeling their guilt of what they did towards you. Don't even mind it.
That being said, it still hurts. You can still physically feel the pain of a broken heart. You were still cheated on, lied to, left for someone else, dropped with no explanation, and are now expected to love again like you've never been hurt. You should never ever forget that being cheated on does not mean you aren't good enough though.
If your special someone made the decision to cheat, they made the mistake of looking for someone new to love rather than finding the love they once saw in you. Wrong move on their part. Personally, I've always been the type to try and make logical sense of each and every little thing, but sometimes, the only logic is... you just got screwed. Not everyone has that cheating attitude. There is absolutely someone for everyone out there. Cheating is one of the most selfish acts you can commit. Do you really want to stay with someone that selfish? You are better off without them, I guarantee it.
When it comes down to it, the mentality of someone with the cheating attribute does not think through the decision logically, which means there is, in most cases, nothing you can do to make them not have the negative, heartless thoughts. So if you can't control it, don't soak in the effects of it. Again, you will be fine, you will be better off, and being cheated on does not mean you aren't good enough.
Your plan now should be to trust the process and focus on being the best you that you can be. So be sad, vent to a friend, let it all out, let time heal you, then enjoy the single life. Try to become a better version of yourself, control only what you can control, stay strong, make them all wonder how you did it, and don't rush into anything you are not ready for. Good things come in time and tough times create tough people. Like I said, I guarantee that if you remain the bigger person, you will come out mentally stronger than ever before.
Pray for your enemies, then watch your attitude change for the better.