I hope he is able to overcome his demons. That being said, you are exactly right. His addiction directly impacts his ability to serve his constituents. For the past month or so, nobody knew where he was, why he dropped out of sight, and when (or if) he would be back. The public was told only that he was being treated for "exhaustion", we should respect his privacy, and that no further details would be provided. Think about it. If any of us failed to show up for work for the past 30 days, refused to tell our employer why, and further stated that our privacy should be respected, how long would an explanation like that be tolerated?
He is among the group that immediately criticizes any Republican for any transgression real or perceived. He needs to live by the same standard.