Yes, Zaltana is right, people only hear/read what they want to in this whole issue, all they see is "Omg they considered trading me, im mad", no it wasnt just like that. When Shanahan was fired, which he shouldntve been, Cutler was upset, who wouldnt be? Look what multiple coaching changes have done to other quarterbacks' careers, alex smith, jason campbell struggled a bit, david carr, theres many more to list so anytime theres a change in philosophy for your position, your not going to be happy about it.
But he dealt with it, and the President/Owner Bowlen PROMISED him that he would bring in a Defensive mind, he broke that bringing in a former Offensive Coordinator from a high powered offense like the Pats. Ok, he dealt with that, but since their offense didnt have much of a problem to begin with, Bowlen then promised him that the rest of the offensive staff would remain intact, then mcdaniels comes in, fires everyone and re creates his own staff, now you have a completely new offense, a new young coach, and already 2 broken promise within the span of a month.
He stuck with it, then the trade talks just put him over the edge, what i see from cutler's side is he saw Mcdaniels as a guy who came in and trid to take over a team that WAS NOT in a rebuilding phase, all they needed was a defense...