"It was a case of me letting myself go and I got myself into a bad situation," he said of the yellow card and straight red he got against Colombia last Wednesday.
"Now it's time to rest my mind and spend time with my family," he told reporters as he left to go on holiday.
"I hope this serves as a learning experience not just for me but for everyone. It's one more thing that happens in my life that I will learn a lot from."
Neymar was handed a four-match ban for the incidents, which were exacerbated by a volley of abuse aimed at the referee after the final whistle had gone in Brazil's first loss for 12 games.
The ban kept him out of Sunday's 2-1 win over Venezuela and would extend to include the final, if Brazil reach it.
The Brazilian Football Confederation (CBF) did not appeal the ban but hit out at CONMEBOL for their harsh treatment of the forward.
"In a meeting held on Sunday night between Neymar and the technical commission it was decided that the CBF will accept CONMEBOL's decision to suspend the player for four games, a ruling that puts him out the Copa America," the CBF said in a statement.
"The technical commission and the player hopes that CONMEBOL adopt the same rigour they used in punishing Neymar in all their competitions." Many Brazilians felt the suspension was harsh given Neymar's reputation and the lack of any violent play.
The player was in the ground on Sunday night to see Brazil beat Venezuela, a result that took them to the top of Group C and into a quarter-final tie with Paraguay on Saturday.
However, the 23-year-old will not be there to support his team mates after what has been a long season in which he stood out for all-conquering Barcelona who won a treble of trophies including the Champions League.
"I think we did the right thing, that I leave," Neymar said.
(Reporting by Andrew Downie; editing by Ken Ferris and Martyn Herman)
