Mindy Hunter (later Hunter-Farber) was Rachel's maid-of-honor in the wedding with Barry, which Rachel walked out of (She had been having an affair with Barry). She married Barry in the season 2 finale in which Rachel was the maid-of-honor dressed—in Chandler's words—as "Little Bo Peep" and "Princess Bubble-Yum". They divorced in season 6 with Rachel saying to the others that Mindy caught Barry cheating on her with another woman. She was played by two different actresses in two different episodes.
Mindy was Rachel's best friend and taught her how to kiss.