Monica Gellar and Chandler Bing have always been friends. They were first introduced by Monica's brother, Ross at a Thanksgiving dinner at the Gellar home. Monica secretely had a crush on Chandler, but he had no idea. He didn't really like Monica, due to the fact that she was fat. Monica decided then that she would lose a LOT of weight and she succeeded! When Chandler came back for Thanksgiving a couple years later, Monica was practically thin as a rail and Chandler couldn't believe it. Due to the fact that Chandler had made Monica feel like crap all those years ago, she, along with her friend Rachel Green, came up with a plan to embarrass Chandler. The plan backfired and Monica ended up cutting off Chandler's big toe.
Fast forward to a few years later when Chandler and his pal, Joey Tribbiani, moved across the hall from Monica and her friend Phoebe Buffay. Chandler and Monica instantly hit it off and became fast friends. Over the next few years, they became each other's confidants and both had many relationship problems.
When Ross was going through his second marriage to Emily Waltham, he took Chandler, Monica, and Joey to London with him to witness his wedding, along with Emily's family (Rachel and Phoebe stayed behind due to the fact that Phoebe was VERY pregnant. Rachel ended up coming to London anyway, but that's another story). At the rehearsal dinner, Monica decided to get drunk when her mother was giving her a hard time about not getting married. She was talking to Chandler (who had made an un-funny best man speech), when one of the guests made a comment to Monica that she looked like Ross's mother. It was then that Monica left Chandler to get drunk. Then, Chandler escorted Monica up to her room and he went to his own room.
Later, Monica came up and she and Chandler got to talking and the next thing you, they both woke up in Chandler's bed the next morning and realized that they had slept together. After that incident occured, Monica and Chandler both realized that they had feelings for each other and became the world's cutest couple (in secret). Since they didn't want to jinx this relationship, they kept quiet about everything. But one by one, everyone began to find out; first Joey, then Rachel and Phoebe, and finally Ross. Over time, everyone got used to it, even Ross, who hadn't taken the news too well when he found out.
Now, Chandler and Monica are engaged and are getting married really soon. Stay tuned to watch out for the wedding!
