Said my spywitness: "Its become fashionable to make fun of Lindsay because she's a train-wreck right now. If she enters a room, it's open season -- and that's how it went down. Paris was with a creep she hangs with -- aka 'the coke dealer to the stars' -- and was in a nasty mood. She's a mess lately, out partying every night since her breakup with Doug Reinhardt. Actually, Paris is out of control herself, but she's better than Lindsay at hiding it."

When Lindsay arrived at Adrian's house, the bullies pounced! Paris whispered to her [drug dealer friend], and he started firing insults like: "OH, LOOK!...HERE COMES DRUGGIE GIRL!"

Said the source: "Paris laughed, egged him on. They ragged Lindsay until she fled to the restroom -- and locked herself in!"

Like wolves on a rabbit, Pairs and her friend "began pounding on the door, taunting Lindsay -- asking if she was 'okay in there'? ... and, 'Do you need anything?...Snort once for yes, twice for no!' Cruel, sarcastic crap like that."