You'll likely have a million emotions coursing through your veins, from anger, to sadness, to rejection, to jealousy. So give yourself time to process these thoughts before you react, and before you confront your partner — since doing and saying things in the heat of the moment is rarely a good idea.

"Although you may be eager to confront them and want to call them at work or accuse them the minute they walk through the door, wait for the right moment," relationship therapist Rhonda Milrad, LCSW, founder of Relationup, tells Bustle. "You want to be grounded and strong so that your message is clear and coming from a place of strength." Also, you owe it to yourself to protect your emotions and do what you need to do to feel some relief, before you proceed with asking questions.

Again, due to heated emotions, it might be tough to think straight or remember things correctly, so make sure that you collect up the evidence, in case your partner tries to deny their actions. "In the following days, weeks, and months you will appreciate having captured the facts so that you will know with certainty what you experienced, even if your significant other challenges or contradicts your memory," says Cullins.

You might even want to verify a few facts, and double check a few things, just to be sure. As board-certified clinical psychologist Paul DePompo, PsyD, ABPP tells Bustle, "If there is no smoking gun, your partner may try to break holes in your evidence so if you can do some minor detective work this can cut through the lies and increase your confidence making you less subject to shady BS."

Find the right time to sit down and "share with your partner what you have discovered and convey the message you are letting them know that you know, and are not asking them if it is true," Milrad says.

And bring those facts and records with you. "Confronted partners often lie, or worse — they accuse their partner of wrongdoing, (snooping, checking up on them, being jealous, being insecure, etc.) and try to make the problem about their partner’s behavior and not their own," Milrad says. Be ready for this, and don't let it distract or confuse you.

"Stay clear and focused that this is about their behavior and stress the fact that you are giving them an opportunity, right now, to come clean, to be truthful, and to stop the lying," Milrad says. "Remind them that more lying will just compound the problems and set you back further. Being strong, calm, and clear is disarming to your partner (they know you are serious) and results in a less dramatic and more honest conversation."

While you shouldn't feel like you need to keep the affair a secret, do think twice before talking about it online, or sharing the news with everyone you know. When you're going through a tough time, talking to friends, family, and even a therapist can be incredibly healing. But it's important to think ahead to the future, and how your words might come back to haunt you.

"Begin with the end in mind," Cullins says. "Cheating doesn’t always spell the end of a relationship. In fact, many couples survive affairs. Before you share the details of your partner’s behavior with others, try to consider how it will impact their perception of your partner if you choose to work things out and stay together. You may be able to forgive your partner, but loved ones may not be as forgiving. Therefore, choose your confidants wisely."

If you do decide to work things out, you'll want to focus your energy on healing things with your partner, and not on explaining to friends and family why you decided to stay.

While it might take months or even years to fully sink in, remind yourself that it's likely that your partner's cheating had nothing to do with you. "Try your best not to critique yourself, to begin the slippery slope of discounting yourself because your [partner] cheated," mental health therapist Maat Petrova tells Bustle. "Your [partner] cheating doesn't necessarily mean you are lacking anything. It doesn't mean you are lesser than the person they cheated with, and it doesn't diminish your value."

So do whatever's necessary — going for walks, talking to friends, chatting with a therapist — to keep your thoughts positive. "While you are a couple and there may be an issue you both need to address, the worst thing you can do is begin negative self-talk about yourself during a highly sensitive and esteem-challenging time," Petrova says. "Speak positive self-loving words to yourself instead while going [through] this infidelity."

Make an appointment with a clinic or your OB/GYN as soon as you can to check for STIs. "Regardless of whether or not your partner admits to unprotected sex, get yourself tested for all [STIs]," says Milrad. "You partner exposed you to health risks and you need to make your health care a priority." While this can be an extremely hurtful and trying time, it is important to put both your mental and physical health first. There is no shame in getting tested for STIs, and it can really help your health in the long-run.

After you've cooled off, spoken with your partner, and gotten the facts, then you can begin the process of deciding if you'd like to stay together or not. Sometimes, the answer will be clear, and you'll have them packing their bags before the clock strikes midnight. But if you aren't sure, or you'd like to try to work on things, it'll be a good idea to draw up a "contract."

"The person who did the betraying needs to create a contract with their partner, which can help their partner feel safe with them if they commit to working on the relationship," mentor Thomas Gagliano, MSW tells Bustle. "For example, if the person [cheated] on them when they were on business trips, then they may need to commit to their partner that they will not take business trips anymore. Maybe they [cheated] with someone in the workplace, then they may need to commit to finding a new job."

Decide together what this contract will look like, and go from there. Whether you're calling things off, or working together to repair your relationship, keep in mind that, even though it sucks, you will get through this in time.