As a partner of a sex addict you minimize, discount, rationalize, deny, and pretend things are different than they really are because you want to trust your partner. You want to believe the relationship has a strong foundation. You want to be able to believe all is okay. That is absolutely understandable. Don't be critical of yourself. If you see the situation for what it really is and don't know what to do, it is natural to slide into a state of hopelessness and helplessness. The truth taps your greatest fear, that you are unloved and abandoned. You feel shame and humiliation. So as long as the addict denies or minimizes it, you can rationalize, deny, and pretend as well. The illusion of safety and security is an enticing fantasy. But in the process you quit trusting yourself, your inner voice.
Denial induces numbness. Now couple your need for denial with the fact that sex addicts are masters of misdirection. They can quickly tap into your vulnerability, and charm you or shame you right out of your distrust. His manipulations may include being charming, bullying, threatening, and playing the victim and often using the combination of any or all of those. This conduct is beyond hurtful. It's cruel, abusive, and traumatizing. It is also a natural aspect of addictive behavior, a manipulative attempt to take the focus off of him.