Very few people navigate infidelity gracefully. Accept that you're going to wobble and fail sometimes. It's okay. The goal here, upon finding out that you've been cheated on, is to take back your power, maintain your dignity and not do anything homicidal.
Here are five things you should never do after finding out that you've been cheated on:
1. Do not confront the cheater until you've gathered evidence. Most cheaters will lie and gaslight you unless you catch them dead to rights, and even then they usually only cop to what they think you already know. If you confront them before you have the evidence, there's a good chance they'll take the affair more underground. Put all your evidence in a safe place. Never reveal your sources.
2. Never accept responsibility for their cheating. She didn't cheat on you because of your penchant for wearing dark socks and sandals in public. He didn't find f**kbuddies on Craigslist because of your post-baby muffin top. Nor did he cheat because you're a bipolar, alcoholic shrew who emasculates him with your rages (although you sound pretty lousy as partners go). People cheat because they feel entitled to. Cheaters are 100 percent responsible for their decision to cheat. If they were unhappy, they could've gotten counseling, filed for divorce, taken up scrapbooking -- really anything other than cheating. They cheat because they value the good feelings they get from ego boosts and affair sex more than their commitment to you and your health and well-being. People cheat because they're selfish escapists. Many of them are quite happy to blame shift their crappy decisions on to you. Don't let that happen. Be very clear on what is yours to own (i.e., dark socks/sandals offenses) and what is not yours to own (i.e., f**king people you aren't married to.)
3. Don't give them any time to "decide." Have you heard the expression, don't make anyone a priority who only makes you an option? You are not an option. You are their spouse. This is not a contest. They made a commitment to you. They don't get to renegotiate the terms. Stalling for time, acting vague about how they intend to make this right, talking a good game and never coming through on the particulars -- these are all ploys to keep them in the affair. You cannot "nice" someone out of an affair. "Oh, I'll just make my needs smaller and smaller, or I'll be so wonderful I'll win them back!" are tactics doomed to failure. All you do with appeasement is give the cheater the green light to abuse you further. The cheater needs to decide right then and there -- or you put their crap in Hefty bags and throw it on the lawn for the raccoons.
4. Do not beg for your marriage. Do not cry or plead or attempt to win them over. Maintain your dignity. When you do the "humiliating dance of "pick me," all you do is feed their egos and give them your power. Now is the time to practice detachment and take care of yourself (see a lawyer, protect your assets, get support). Set aside your grief and make room for righteous anger. Let it fuel you forward. You are not anyone's consolation prize.
5. Do not waste your time trying to figure them out. Seriously, people, this is a time suck. I call this stage "Untangling the Skein of F**kupedness." If you're like most betrayed spouses, you spend a lot of time in pointless arguments yelling at your cheater, "WTF?! How could you do this?" or "Does she have some gravitational pull that you're helpless to resist?!" or "That fedora-headed, hipster douchebag? Really?" You'll posit theories. You'll deconstruct their family of origin issues. You'll order a dozen infidelity books on Amazon. All this does is keep your energy focused on them. Not you. You only get to control yourself. So what do you want? Is this person someone you want to invest in? What is acceptable and unacceptable to you? And what are you going to do about it? If you're so busy trying to uncode them, or predict what they'll do next, or prevent them from doing some awful thing, you will just stay stuck. It doesn't matter why they are how they are. You can't fix it. You just get to fix you.