>>717948047miller was assblasted at all the lying a deceit that went on. he was plagued by paranoia, thinking that everyone else was in some grand scheme against him. when he found out about venom being a decoy, he again felt betrayal. venom kept making decisions that miller did not want to happen at diamond dogs like not killing quiet. while he respected venom, the paranoia and betrayal when he found out that venom was not big boss hurt him gravely and made him question everything he's been doing even more. he also felt wounded that big boss just left him after all this time and never came for him or even let him know the plan.
the problem is that all of this is in late/post game cassette tapes and requires piecing together the arc from cutscenes and cassettes after 50+ hours of gameplay that are sparsely peppered throughout the experience while other narrative threads are much more prominent, distracting you from miller's story.