Unless one counts the orbital flights of the command module Columbia, while the landing module Eagle, was on the surface of the moon, there have been no solo flights to the moon. The Apollo series of flights ending with the moon landing on July 20, 1969 were all multi-crew flights, as were all Russian flights...
Apollo 11 also orbited higher above the moon than subsequent flights, so Michael Collins also holds the record for being the person most isolated from his fellow man (Armstrong & Aldrin) who were the diameter of the moon (2160mi) plus orbit height (60mi) away (2220 miles total).