You've had a lot of replies and you sound like you've made your mind up, to an extent. I think you are right to not move in, as that in itself will affirm to his subconscious that it's not a problem. Whether you end the relationship entirely might depend on whether he can acknowledge he has a problem, accept it, AND make a change. My partner was a weed addict, and he no longer is... But it took a lot of my support, a lot of pushing for it, and putting things in place which made it possible for him to stop. Addicts don't tend to do well with less support. It did take years, though.
I also have experience with AUD (Alcohol Use Disorder). My late father died in a very undignified, scary and upsetting way from liver cirrhosis after starting out as a functional alcoholic. He chose alcohol over my mum, me and my brother, and that has scarred me more so than watching him die from it. I've also got a mild to moderate AUD which got it's claws in when my dad started to get very poorly, although I've always loved the affects of alcohol due to an anxiety disorder which I've had since childhood. Thanks, dad 👍🏻
However, despite knowing first hand the impact of drinking, until I did the AUDIT-C (Alcohol Use Disorder Identification Test - Consumption) on ChatGPT, I had conflicting thoughts about the severity of my drinking, and the treatment I needed.
My own therapist told me that it didn't seem too bad due to the fact that I was functioning, it's only 3 nights a week, I only drink in the evenings, and I can go days in between. She was trying her best not to shame me, but that advice was completely wrong for me, given that alcoholism has a hereditary component. I decided to stop seeing her, because 'just being kind to myself' is what made me drink in the first place.
I got on ChatGPT and wrote down the facts (which was hard to pin down accurately at first, even to an AI robot!) about how much I drank, what I drank, how long I'd been drinking and why it started.
Having it put in a factual and non-shaming way helped me see things clearly. I didn't need to go to rehab, have a community nurse, or take naltrexone and acamprosate. I needed to go back on my SSRIs and go cold turkey, and get a new therapist.
There are different reasons people drink and having an understanding of why your partner drinks, when it started and his family history is crucial if you end up sticking around.
When you bring the discussion up to your partner later, and he begins to minimise his drinking or tell you that it's just your opinion that he is drinking too much, get onto ChatGPT and say "okay then... Let's put all these facts into a non bias computer and see what it says". If goes along with it, I'm sure he will chose answers that minimise things or straight up lie... but you have been keeping an eye on his units, so you could actually do the test for him based on the facts in advance to equip yourself. If nothing else, his reaction to you shining a spotlight on the facts will show you how tight his relationship with alcohol is.
You don't have to help him with it, but don't let him gaslight you and try to convince you you're wrong. My dad claimed he never had a problem, even when he was having seizures in the hospital from withdrawal.