A spouse is dealing with their husband's or wife's addiction, even if they don't know about it. Because whether you recognize it or not, if the addiction is there you will react to it.
It's like the Elephant in the room. Even if you don't see the Elephant to know what it is, you will see the crushed furniture, you will smell that beautiful aroma (gross) and you will hear some weird sounds.
Ok, that's a bad example. But it fits. Even if you don't see the addiction to know what it is, you may notice things like moodiness, lack of empathy, you may hear stories that don't quite match up. Things like that.
It may sound weird, but this comforted me a little when I found out about my family member's addiction. Why? Because up until finding out about the addiction there were a ton of seemingly unexplainable things. He would fight with me over the strangest things, he would be moody and get upset over things like me asking if he could grab me a drink of water (when I was sick and pregnant). These things made me feel awful and worried about why our relationship was struggling like that. I hated being growled and grunted at. Yes, growled and grunted at. Literally: GRRRRRRRRRR! A deep, gutteral sound from the stomach... Just a few examples of my personal experience.
Finding out about the addiction was like a puzzle piece for me. An aha moment. The comfort came in knowing that all of those things were NOT NORMAL. That there was a massive influencing factor. That maybe it didn't have to be like that forever.
Because there were even bigger influencing factors, I am no longer in a relationship with this person. But, even so, I am grateful for this knowledge that all of those things that happened before finding out about the addiction were NOT NORMAL. As a friend, a spouse, a parent, a kid, it is good to know that that those kinds of things should not be a part of your relationship. Our relationship was never given a normal chance because the addiction was always a part of it, I just didn't know it. There was nothing normal about our relationship. Which helps me to put things in perspective.