"I don't think I deserved such treatment at United - not playing (regularly) in the last year," Berbatov said at Bulgaria's Vasil Levski national stadium in Sofia.
"I went more than 10, probably 15, times to ask the coach if they need me. And every time I was told that I'm an important player and should not leave, but then again I was not in the team.
"Maybe I should've gone when he (Ferguson) left me out of the squad for the Champions League final (in 2011). I know he's the boss, but he has lost, to some extent, my respect because of the way he treated me."
Berbatov spent four-years at Old Trafford, becoming their most expensive signing when United took him from Tottenham for £30.75m.
During that spell, Berbatov was the Premier League's joint top scorer during the 2010/11 season with 20 goals. Yet last term chances were few and far between - which was due to a change in style at Old Trafford.
"He (Ferguson) tried to explain to me that the team will be using a more direct style, with more speed," Berbatov said today. "But I've never been among the fastest players, I like to hold the ball, this is my style.
"I found it hard to accept his decision (not to play me) - I still have my dignity. I scored many goals, I won the league two times, and I was the league top scorer, so it's not bad.
"I'll have no problems playing against United as this already happened in my career. But there's no point to look back again. I said goodbye to the people, who deserve it. I couldn't say goodbye to Ferguson."
The transfer of Berbatov was among the most speculated of all the deadline-day moves - with the 31-year-old linked strongly with Juventus and Fiorentina - the latter of which was furious when no deal came to fruition.
"He did not deserve our city and our shirt and the values it represents," Fiorentina said in a statement after the transfer fell through. It would seem Berbatov does not feel responsible.
"I've never personally told them, 'Yes, I'll play for you'," he said. "It's not my problem that someone is disappointed. After all, I choose where to play and be happy."