Complex sentence: Her close friend and advocate, the painter Tony Bechara, attended a dinner with Frederico Sève, the owner of the Latin Collector Gallery in Manhattan, who had a much-publicized show of female geometric painters from which an artist had dropped out.
Split into simpler sentences: Her close friend and advocate, the painter Tony Bechara, attended a dinner with Frederico Sève, the owner of the Latin Collector Gallery in Manhattan. Sève had a much-publicized show featuring female geometric painters, from which an artist had dropped out.