Wenger clearly feels sorry for Diaby. In the end it the day this is a player that has had his career destroyed by a disgusting, needless challenge by Dan Smith in the last minute whilst Arsenal were already 3-0 up against Sunderland.
The same type of challenge that spawns equally as reckless and outdated comments such as "He's letting him know he's there" from our mainstream media (ITV, Sky and BBC pundits).
Wenger didn't want to discard him, he wanted to give him the best possible chance to recover, which it seems has failed.
Dan Smith for the record, is now without a club at the age of 28. He last played in the 5th division of the Australian league for Holland Park Hawks.