Valverde is sure to come under fire despite winning back-to-back La Liga titles, having also seen his team give up a lead against Roma in the quarter-finals last season.
"We are now very hot because of the elimination," he told Movistar+ .
"Now, we have to raise our spirits because there is a final of the Copa del Rey to play in.
"They will be difficult days for everyone, but we have to get up."
Braces from Divock Origi and Georginio Wijnaldum led Liverpool – without star forwards Mohamed Salah and Roberto Firmino – to their win.
It came just over a year after Barca suffered a 3-0 loss in the second leg against Roma, giving up their 4-1 advantage.
"There will be time to reflect and explain," Bartomeu said. "There is a Copa del Rey to play in three weeks.
"Last year, in Rome, the same thing happened, difficult to explain. We will do it internally. Now, it's time to play the Copa del Rey, lift the mood and apologise to all fans of Barca."
Valverde himself said he hadn’t had time to think about much but admitted that responsibility ultimately falls on the coach.
Barcelona have two more La Liga matches and plenty of time to recover before taking on Valencia in the Copa del Rey final on May 25.