This question is indeed a tough one so your choice and reasons should be right. Sometimes, the pressure from family and friends telling you to walk away from the relationship may be too much that you are pressurized into doing it but in the end, you will feel bad or regret your actions. There are certain steps you need to take to reassure yourself that indeed you are on the right path of accepting your spouse and signs too for you to realize that he/she needs another chance again with you.
1 Forgiveness comes from the heart so if your spouse becomes a better and trustworthy person than before after opening up about his/ her infidelity then you have to reconsider a new beginning with him/ her because it shows they regretted it and will never indulge in the act anymore.
2 Before considering the big step of separating from your spouse, find out if truly it comes from your heart to do it. Are you ready to let go? If the answer is no, then quit having thoughts or plans on walking away because you are still interested in staying so work on how to improve your relationship with him/her.
3 If your partner is open and truthful with reasons why they cheated, you just have to realize that your spouse accepts their wrongs and feel guilty about it. Whatsoever reasons they give, know that they are remorseful about it that is why when you ask questions, they don't hesitate to hide anything from you no matter how dirty the secret is because they are willing to answer and earn your trust in the relationship again.
4 It's a good sign to reconsider having your spouse when he/she suddenly take challenges to make the relationship with your work. They start engaging in new creative activities that will make you see they have become a changed person.
5 Choose love over justice even if you felt betrayed or hurt by your cheating partner.if you find out that you are still deeply in love with your spouse, you can't just let go.
6 If you discover that you don't feel hatred, bitterness or have grudges in your mind to retaliate by also cheating on your spouse then its a good sign you want your partner back. It is much better if you don't like to hurt your partner by reminding them of their cheating mistakes or mentioning it to them, it's a sure signal that you want to give your spouse a second chance.