Welcome to the group and your story is not a new one here. Most of us spouses have lived through the secrets, the lies, the minimizing, and having it all turned around on us with blame and judgment so, if you do bring it up to him, be prepared. He will be very defensive and probably blame you for being paranoid and snooping.
Do not ask him questions about it. State the obvious to him and let him know that when he is ready to open up to you about his behavior, you will listen and be supportive of his efforts to recover.
If he has been having sex outside of the marriage, please get tested for STDs. More often than not, addicts will not even consider using protection.
It sounds to me like this has been going on for many, many years, probably longer than you know. He has reached a stage where sex with women isn't enough for him and men are much more accessible. This is not necessarily a sign that he is a homosexual, but this addiction has far reaching consequences. He needs serious help.
In counseling, you will need to face the issues head on in terms of what you can do for yourself. Building boundaries and safety nets in your home is paramount to your well being, even if that means him having to move out. In no way can you send him a message that this is acceptable to you. He needs to understand that this is not your value system and if he wants to continue being married to you, he needs to get into a recovery program.
These should be your goals and it will not happen over night. Take your time assessing your situation and make decisions in a timeline that works for you.
Keep us posted as to how you are doing. You are not alone here.

Thanks you so much Shanas1254. I appreciate your thoughts. It is hard to vacillate between total anger and compassion and love for someone who is just not making wise choices. I do need to take time to process all of it and not jump too quickly which can make things worse. Now that I have the ability to see his computer, it is hard to know if that is a good thing or a bad thing. I feel I want to know the truth, but I also don't want to be obsessive about things. two weeks ago we did have a nice candid talk and he said he thinks he needs to just stop looking at any porn because it is a waste of time for him. Apparently, that did not stick. I know he has always suffered from low self esteem, and I cannot think this situation is helping him at all. I have to just do more thinking of myself but when you have been a selfless wife for so long, it is hard. It helps to know my journey is not unique, but it sure is not a path I would have ever chosen or wished for.

Please understand that this is a serious addiction. Most sex addicts think it isn't and they can just stop. It doesn't work that way. They do need a recovery program just like other addicts. Here is a good website that helps people understand the impact of watching porn on the brain. It was a real wake-up call for me to see that there was an actual chemical imbalance that happens over time. Things can return to normal in the brain, but one must refrain from watching porn in order for that to happen, among other things. www.yourbrainonporn.com

Thanks again. The more I learn, the more it is so scary, and I am so grateful I don't have this problem for myself. Dealing with it with a loved one is hard enough. I did share a couple of weeks ago with my husband about how the brain chemistry can change and he said he would just stop it. that lasted maybe a week. I have not revisited it with him. I have no idea if he is trying to stop or just trying to fool me. I can see this can be a long journey.

i am so sorry you are going through this...relational betrayal is the worse and causes so much trauma. its time for you to set some boundaries within your home and your marriage. You already know that he is betraying you with porn at the least He could be doing worse and like shanas said no matter what dont take his word for it and get tested.He has shown in the past that he will have sex with other women so he could be again.

Tell him you know what he was doing ...and then tell him how it makes you feel. be prepared you will excuses and lies. set boundaries...and consequences and tell him this as well.

know you are not alone ..sex addiction is rampant and is destroying lives and marriages...he needs help and you need support. you also need to know that no matter what you dont deserve this...

Hold on to yourself this is going to hurt like hell.... I am still getting denial and I know.. I stopped caring if he was pissed... he's lying to me and ddoesn't seem to bother him and I will not feel guilty for wanting an honest relationship... ur not doing this because u are trying to punish ur doing this because u can see it, it's right in front of u... don't allow yourself to be played cause it will not hurt as much that way... it ends up hurting worse.. my husband's first betrayal was 18 years ago.. looking over the years I have been so blind.. I can't wait anymore I am going to do another 18 like this... no thanks.. I am sorry that this is what it is... but accept and then love yourself like all that energy you have spent on him u deserve it... hugs

Thanks for the kind help. I am doing my best to not take all this personally even though that is hard. We watched the brain on porn movie today on the premise it was for a friend, He was interested. He fell asleep on the middle but asked for the link. I sure hope knowledge is helpful to him. He said he had never heard of this before. For now I want to keep a close eye on the situation and pray he will get convicted to become clean. I will do my best to take care of myself and remain grateful I do not this infliction. thanks again everyone. I'm sorry others have gone before me.

Also try www.recoverynation.com. Both addicts and spouses can work together and separately in their programs online and get the support needed. It is a worthwhile program, especially for those who are not ready for face to face meetings.
My husband also started with http://candeobehaviorchange.com/
This was a great program to begin with, but for him it didn't take him far enough and that's when he joined a 12 step program. But again for those who are not ready for that, these online programs are very helpful and do offer support.