Richarlison felt Brazil's World Cup quarter-final defeat to Croatia was "worse than losing a family member".
Pre-tournament favourites the Selecao won Group G and thrashed South Korea 4-1 in the round of 16 to raise hopes they could be crowned champions for the first time since 2002.
The loss sparked emotional responses from a number of players with Neymar, who had given Brazil an extra-time lead before Bruno Petkovic's equaliser sent the game to penalties, left in tears on the pitch as Croatia celebrated their victory.
Richarlison told ESPN: "It was a blow, I don't know. I think it's worse than losing a family member.
"It was difficult to recover. To this day, when I watch videos on my social networks, it makes me sad.
"But we have to move on. I'm still young, I think I still have one or two World Cups to go. I will keep working hard so that things start to flow again, the goals start to come out, which is what I know how to do on the field."
Despite the disappointing end to the tournament, it was a strong World Cup for Richarlison, who was Brazil's top scorer with three goals.
The Tottenham forward's bicycle kick against Serbia won the goal of the tournament award and has also been nominated for the 2022 Puskas Award, handed out by FIFA to the best goal of a calendar year.
"Our goal was to be champion. I scored a beautiful goal, but I think that goal, let's say, was not my goal," Richarlison added. "We went there to raise the cup.
"But I'm also happy to have scored that great goal, even running for the Puskas. I was happy, because I think a lot of people started to know me more. It was very important in my career."