Fernandes has been targeted by a wave of social media abuse following Portugal's World Cup elimination, with the Manchester United captain turning off replies to his first post since the 1-0 round-of-16 defeat to Spain.
Portugal's exit, sealed by a Mikel Merino stoppage-time winner in Arlington, brought an end to Cristiano Ronaldo's international career and left Fernandes among several senior players facing intense criticism from supporters online.
"Sad, frustrated, and disillusioned," Fernandes wrote on social media. "This group of players made my expectations high, not only for the quality, but also for the fact of the incredible group that we built over these years.
"Thank you to all the players, technical team, and all the staff who accompanied and helped us every day during the World Cup. To all the Portuguese, a huge thank you for your support and belief."
The 31-year-old, along with team-mates Vitinha, Joao Neves and Pedro Neto, had already been accused of "sabotaging" Ronaldo's swansong following a drab 1-1 draw with DR Congo in the group stage, with the criticism intensifying after the exit against Spain.
Tension around Fernandes had been simmering since the tournament's opening match, when Ronaldo's sister, Katia Aveiro, liked an Instagram post accusing the Manchester United captain of failing to deliver in a Portugal shirt, comparing him unfavourably to under-fire Brazil forward Raphinha.
Aveiro had also posted her own criticism of the team's performance after the DR Congo draw, writing: "Magically, they forgot how to: pass the ball; win it back; launch counter-attacks. The game became all about passing backwards in midfield... strange World Cup. Very strange."
Her posts were widely interpreted as fuelling talk of a rift within the Portugal camp during the tournament.
Fernandes arrived at the World Cup off the back of a Premier League season in which he became the first player in the competition's history to record more than 20 assists, and has long been one of Portugal's most important players, with 94 caps and 29 international goals.
Head coach Roberto Martinez had resisted pressure to drop Ronaldo throughout the tournament, but the criticism aimed at Fernandes and his midfield colleagues reflected wider frustration among supporters at a side that had entered the World Cup among the favourites but were unable to get the best out of their captain in his final appearance on football's biggest stage.