Ben Affleck and Matt Damon really are best friends forever. Affleck, 53, and Damon, 55, reunited at the Tuesday, January 13, premiere of their new film The Rip in New York City, opening up about what they are learning and relearning about each other as they continue to work together over the years. "I keep relearning things about Matt that I already knew and I forget them," Affleck, 53, joked to Us Weekly exclusively before getting serious about their decades-long friendship. "Honestly, I am continuously reminded of what a great father he is and what a fabulous actor he is.