Hello - There are s-anon meetings available online to help you deal with living with a sex addict.
Cheaters can use the disease of sex addiction as a manipulation....a way to avoid taking full responsibility for their actions (poor me, I have a disease) OR they can really have a sex addiction. If you go to the SAA website, there is some good information about identifying as a sex addict. Your husband also needs to see a CSAT for a diagnosis. If he does indeed have an addiction, it is a rough road. If he is not fully committed to SAA meetings, consistently and for the long term, getting a sponsor and doing the work necessary to maintain sobriety, he may very well relapse. The relapse rate is high for SAs and living with an active addict is misery (as you know). He will also need to have therapy with a CSAT, who can help him develop the tools necessary for sobriety and to keep you safe.
SA is a process, or behavioral addiction, like gambling. With other addictions, abstinence is the answer. For example, I have been in recovery for alcoholism for many years. I abstain from alcohol. If I had to take a drink once a week to maintain my marriage, I would relapse. For an SA, the very behavior they are addicted to is necessary for a healthy relationship. This makes it super hard for an SA to stay sober for the long term.
This man has been lying to you, to himself and most likely to his therapist since d-day. He did not come clean to you, you found him out. He has been hiding this from you. This means that he is not ready to get sober on his own and he is not currently a good candidate for R. That is why you are seeing the manipulation. He is fighting for his dysfunctional coping mechanism. If he was truly remorseful and ready for sobriety, he would have been honest. The medium (hentai, photographs, video) is not relevant. The compulsion and dishonesty are. I liked red wine. That does not make me a classier drunk than the guy on the street drinking malt liquor. It makes me a drunk. Period. No rationalization will make him better than any other addict. This is important for him to realize.
I know from personal experience that porn addiction, like any other addiction, will progress. In my husband's case, it progressed into affairs. Over time, the "high" from porn is not enough stimulation, so sex addicts go from more and more intense porn into actual sexual acting out (dating sites, escorts, massage parlors, exhibitionism, etc.). Please be careful of your health. If he was lying about the porn, he may be lying about other activities. Have you checked the money to see where it is going? I hate to be negative, but my purpose is to give you the knowledge you need to choose the life you want. Knowledge is power.