The Frenchman tore his anterior cruciate ligament last month, and will now miss the next eight months of action having made just 15 appearances this season.
Bould is hoping that the 26-year-old, who missed all but five games for the Gunners last term, will come back an even better player.
"I've spoken to him very briefly. I saw him just before he went for his scan. It's dreadful news for Abou," Bould told London 24. "As we all know, he's had seven years of injuries and it takes a huge character to come back.
"Maybe it's a chance for him to correct everything that was going wrong. He might use the seven or eight months to get rid of all those injuries that he was struggling with.
"We're all hoping and praying that he comes back a better player. Abou has to use this as an opportunity to work on all those bits that keep breaking down. That's the positive that he can go forward with."
Diaby joined the club in January 2006.