Dunne, who joined Villa from City in a £6miillion deal earlier this week, admits he is disappointed over the way Cook tried to sell him.
He explained to The Sun: “From the day after the Bulgaria v Republic game in June, I was getting phone calls from people saying Garry Cook has been trying to sell me behind my back.
“That was two months after me going to him and saying if he has any problems to come and deal with me.
“I’m disappointed with people who say one thing and then completely do the other. I’m not a baby, I’m not going to cry just because the club want to sell me.
“I don’t mind, just don’t do it behind my back.”
Dunne continued: “Garry Cook has come in and he doesn’t really understand football. All he wants is big-money players. He doesn’t understand the core of the club and where it begins.
“For him, I was probably a bit of a nuisance, I obviously found out things that were going on behind my back and I wouldn’t speak to him.
“Every time I came around he probably felt a bit uncomfortable. I just feel really bad because I don’t want to sound really happy about leaving Manchester City.
“My only problem is the way they dealt with it.
“I have been honest enough and loyal enough with them – they should have been the same with me rather than doing stuff behind my back.”