On March 18, 1990, two guys dressed as Boston’s Finest pulled off the biggest art heist in US history. Holes in Gardner Museum’s so-called security led to holes in frames. I commiserate with those who may never tick that Vermeer off their bucket lists. But mostly I feel for Isabella. I’ve had a close, imaginary relationship with this woman since the day I arrived at college literally next door. Museum admission was free back then, so I frequently strolled through like an invited guest, taking in Sunday concerts that seemed arranged just for me. In my yearbook picture, I’m seated on a bench abutting the Venetian courtyard, my hair ironed and my glasses off,…