Everton winger Bernard defended his "dedication" after joining Sharjah FC in the United Arab Emirates on a two-year deal.
The Brazil international, 28, joined the Toffees in 2018 on a free transfer after leaving Shakhtar Donetsk.
Bernard made 73 Premier League appearances in three seasons, scoring five goals.
He thanked fans and "players who were with me" but said "you don't know half of what happens behind the scenes".
Everton confirmed the transfer on Saturday, two days after Sharjah's announcement, saying: "The paperwork for the Brazilian forward was finalised on Saturday despite Sharjah announcing the transfer on Thursday."
Last summer, Bernard said he had been seeing a psychologist for a year after an anxiety attack.
In a social media post, he added: "Since I arrived [at Everton] I was always well received and treated as if I was really a member of the family.
"Unfortunately you who support me, and not those who appear here to spread the words of hate, don't know half of what happens behind the scenes. I wanted to be more clear but unfortunately today I can't.
"The message I leave today is of gratitude and you will always be special. Everton is giant, has an incredible history and has the structure and capability to return to be and to conquer everything that it has been and conquered.
"I'm satisfied about how much I dedicated myself and did my best to be the best of me in all training and games."
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