David Barton celebrated 20 years of running gyms while his quasi-former wife, Susanne Bartsch, celebrated her 61st birthday the other night at the Copacabana. The guests, about 300 costumed club “kids,” celebrated because that’s just what they do.
“I love you all,” said Bartsch, taking the stage around midnight Thursday in a long black dress with a back slit exposing a hint of butt cleavage ...