rose-tinted spectacles
An unduly idealistic, optimistic, sentimental, or wistful perspective on or about something. Primarily heard in UK. I know Sarah looks on our childhood with rose-tinted spectacles, but I can't put aside how difficult my parents' failing marriage was for all of us. Despite doing worse every quarter for the last two years, our boss keeps seeing the business through rose-tinted spectacles. You need to take off your rose-tinted spectacles for a moment and realise that there are serious problems in the world that need fixing.