The Catalans suffered a 1-0 extra-time defeat by their arch-rivals in the King's Cup Final on Wednesday, days after being held to a 1-1 draw by 10 men in the league at the Bernabeu.
Jose Mourinho's side deployed a physical counter-attacking approach which unsettled Barca in both games, and Guardiola was asked if he was considering changes to his system for the third and fourth clashes between the sides over the next two weeks.
"It's as if our style has become an excuse for us having lost the Cup final," Guardiola told a news conference.
"Whether you win or lose, the style is always the same. Playing attacking football is the only way I understand, it's our club's philosophy and I'm not going to change it.
"We are going to attack and to try and score goals at the Bernabeu."
The softly-spoken 40-year-old, who won a treble with Barca in his first season at the helm in 2008/09, became riled when it was suggested that only winning La Liga for the third year in a row might be considered a failure.
"It would be a disaster, a failure, it would be necessary to change the president, the coach and all the players. The cycle would be at an end," he said ironically.
"We are up against a recent past where we had a lot of success. I would be happy if we only won La Liga but if the fans are sad, what can I do?"
Barca hold an eight-point lead over second-placed Real in the league with six matches left, starting with the visit of relegation-threatened Osasuna on Saturday.
Guardiola had no time for talk of players suffering damaged morale.
"The players need to react because it is their job to," he said.
"If they are angry or sad they should run more, that way they'll get over it quicker. Those feeling sorry for themselves can go and sit in the stands.
"In sport, you lose more than you win. I'm not a psychologist, I'm a bloke who played football and who qualified as a coach. Nothing more."
Barca visit Madrid next Wednesday in the Champions League and play the semi-final return leg at the Nou Camp on May 3.
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