A then 33-year-old Villas-Boas was appointed as Blues manager during the summer of 2011 before being sacked in March 2012 after the club was struggling to hold down a place in the top four of the Premier League.
Alex believes that Villas-Boas showed senior players "a lack of respect''.
"The work of Villas-Boas on the field was very good, the players accepted it well. He has a style similar to that of Mourinho," he said.
"I ended up being turned away by him, but to this day I know I did not make any mistakes, neither against the team nor against him. [Nicolas] Anelka and I ended up apart, we were training separately. But it's soccer stuff, it's already in the past...
"I did not expect all that. I did not even expect to leave Chelsea. What people said a lot was his lack of respect, especially with [Frank] Lampard. He put Lampard in reserve and did not say anything.
"A player like Lampard or Terry is not that you have the need to justify yourself to them, but it's important to have a conversation. I also saw Ancelotti and Guus Hiddink putting important players in reserve, but they always talked to them before."