PRO ANSWER

Hello. Firstly, I want to say that this must be terribly painful for you. Not only do your husband's actions speak to betrayal of enormous magnitude, but his behavior also speaks to emotional abuse, which is an insidious crime simply because the wounds that are present within you are not tangible to the naked eye. It is imperative for you to come to terms with why you allow yourself to be treated this way. Despite what he does, you must not allow your integrity to be taken away from you. No matter how many years you have invested into a relationship, it is not so much the loss of the person as it is rather the loss of all the hopes and dreams that have yet to be manifested in that relationship. That is the grieving. Your husband can do what he wants because he can. You must take steps to get out of this relationship and find yourself again with utmost honor and reserve. Remember who you are. Sometimes everything we want control over we have none. Yet, what you can control is loving and honoring yourself, addressing what your needs are for yourself and staying on a path that speaks to that. Attempt not to put so much energy on what he does. Raise your bar and put one foot in front of the other slowly. Once you put your energy into a positive mode, somehow, you will be provided for and all that is suppose to work out does. Do not focus on the outcome. Save yourself, get angry and move on. By you staying in that predicament allows you to continually to be abused and unnurtured. Only you can change that. Believe me, once you do, you will have a glorious freedom that will lift you and free you from this pain. Don't you deserve that?

PRO ANSWER

Affairs can be very damaging.  Affairs are unfair.  The spouse that is having the affair talks to the other person about all the problems in the marriage.  That person affirms that the affair spouse is all right and the spouse is all wrong.  What you feel as the spouse being cheated on is all the pain and all the blame while your spouse is much too comfortable.  It will seem like nothing you do is right no matter how hard you try. 

This is the best way to explain the damage that emotional affairs do in a marriage.  Imagine a seesaw that is level.  Now image one person climbing on one end and two on the other.  The person on one end gets left dangling helplessly  while the two on the other end have total control.
In order for your marriage to work out your spouse will need to end the affair.  If your spouse does not then your marriage is doomed and you will be left crushed on the ground while the other two waltz off the seesaw. 

If you suspect cheating, it is okay to look into your spouse's private affairs such as email and cell phone to check for messages from one consistent person of the opposit sex.. Once trust is violated then privacy goes out the window and your spouse no longer has a right to it until trust is earned back. 

It is okay for you to find out where he goes, what his work schedule is and what time he is coming home.  It is okay to call his work and find out what his work schedule is if he refuses to tell you.  It is okay to let him know that you suspect an affair even if you don't have concrete proof.  If he denies it even though it looks to me like it is pretty clear that he is, then you can show him the evidence that you have gathered so far.  Your marriage will not survive as long as he is in this affair.  He has to choose one of you and you have a right to demand that.  The two of you can recover from this affair if he chooses to remain with you however he has to cut all ties with her.