1. Talk to your spouse.
You need to figure out how to address the problem with your spouse. It may be enough to just say, "Honey, there's something we need to talk about," and you explain your concerns to him. But if he refuses, you've got to be prepared.
Sometimes confrontation may be necessary to stop the affair. You can say things like, "I've noticed you seem emotionally distant from me lately," or, "I feel like we're not spending as much time together as we used to."
If your spouse draws further away, it's probably a sign that he/she is involved in an affair.
2. Seek help online.
There are numerous methods available for addressing an affair online. You can try a help or support group such as eNotalone for suggestions. Many people there have dealt with breakups and marriage struggles, and it helps to have others who know what you're going through.
You can also talk to a close friend or family member to get emotional support. This can often be enough to give you the courage to actually sit down and talk with your spouse about the problem.
3. Make note of his habits.
When you suspect him of an affair and you decide to confront him, you need to actually have proof of your suspicious. If you've caught him spending a lot of time online talking to someone else, you have a right to know what's going on.
Don't be afraid to question him about his online activities, or who he's spending time with. Marriages must be founded on mutual trust and honesty; if he's not being totally honest with you, it's possible he's having an affair.
The bottom line is: you must talk to your husband and find out what's going on when you want to know how to stop an emotional affair. If you don't actually speak to him, you'll be going down the same road he is, of being sneaky and dishonest.
So confront him and use each of these points as the basis for your decision.