This kind of sounds like a lack of communication.
Also, people who are in active addiction and people just coming out of addiction (attempting sobriety/addiction) can be in a really precarious place. I hope you will read around the site, including the newcomers to recovery forum and kind of get a glimpse of that.
All that is to say, attempting recovery from addiction is a huge big deal and he may have no idea what he wants right now.
That could be part of it.
The second part, the communication, he may well be attracted to you and when you were coming to visit, all bets were off, he had to tell you about his recovery plans because he does not want to be in an actual relationship right now. When you were somewhere else, that wasn't an issue. It's not exactly the best approach, for sure, in my opinion, but perhaps he thought telling you face to face was good timing? Was this visit planned for a long time? Maybe he thought you wouldn't be visiting so soon and he wanted to see how things would go?
You can't know though if you don't ask him.