Oliver: I'm looking for a way in.
Diggle: I was furious to think that you trusted Malcolm Merlyn more than you trusted me, but then I realized that I'm not angry with you, I'm angry at myself for thinking you're someone that you clearly aren't.
Oliver: I don't know what that means.
Diggle: Oliver, after everything we've been through, man, I couldn't fathom why you didn't trust me. Then I realized you couldn't. It's not who you are. You don't trust. You don't love. You were able to fool Ra's and join the League because inside you are every bit as dark as they are.