France are in pole position to win the championship, but England and Ireland are still in contention if Les Bleus slip up against Scotland.
"It is difficult," said Leinster back row Van der Flier as he analysed where Saturday's defeat went wrong for Ireland.
"I think one of the things I find that's really important is you have to get all the misery out of the way on Monday or Tuesday, so it's not hanging over you for the rest of the week.
"Those things are hanging in the back of your mind and you can't let them drag into next week."
After the disappointment in Dublin against France, Van der Flier says Ireland have to "put in a performance to be proud of" against Italy.
"That will be the focus I think. We have to put in a performance to be proud of," said the 31-year-old.
"Obviously for the team, the pride of playing for the country, but also the opportunity of potentially winning the championship
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