The 26-year-old started both Arsenal's fixtures over the past week after more than three months out with a thigh problem and is set to feature in a holding role behind Jack Wilshere again at Chelsea on Sunday.
It was the latest in a long line of fitness issues for the combative Frenchman, who had recovered from a potentially career-ending broken ankle after a tackle from Sunderland defender Dan Smith in May 2006.
And Wenger feels a fully-fit Diaby can emulate midfield enforcer Patrick Vieira and help drive the Gunners on as they aim to claw their way back into the top four of the Barclays Premier League.
"Honestly, what he has gone through is unbelievable," Wenger said.
"It is frustrating because it all started with a bad tackle at Sunderland, in the last minute of the last game of the season, which was decided already. You always think 'how can one thing that was so stupid can have such an impact on a career of such a big player?'.
"This now is a big period for Abou, and he is conscious of it.
"You do not want to put any pressure on him, though, because he has enough and Abou puts himself under so much pressure.
"He is a very conscientious guy. You should see how he works, how he is focused every day, because when a guy suffers as much as he did he becomes very professional, very rigorous.
"You have some guys, they can drink five beers, come to training, and play and go home and nothing happens to them."
Wenger added: "When you have a guy who is a lot injured, and he has not a serious life, you can say 'you see, you are punished', but with Diaby, he has a very serious life - he doesn't drink, doesn't smoke, doesn't go out, and is very conscientious in training, so you always feel sorry for him.
"You are in a position where you have to have patience, because what did he do wrong? Nothing. At least you have to give him a chance."
Wenger feels Diaby gives Arsenal's game a "different dimension" - much like Vieira did when his Invincibles swept all before them in 2003/04.
The Gunners boss said: "Abou can defend, can attack, is strong in the challenge.
"He can also dribble, pass players, is very quick in the transition from defence to attack.
"This guy is good in the air, is a fighter, with great stamina, so once you put all these qualities together... when he plays at his best, of course, Arsenal have a different dimension."