Margaret Cho -- Virgin America Humiliated Me And My Disabled Friend

Margaret Cho is going full blast on Virgin America ... claiming the airline humiliated her disabled friend.

Selene Luna -- a little person recovering from a debilitating hip condition -- opens for Cho. According to Cho, Luna was trying to pre-board a Virgin flight with her when she was rudely dismissed by a ticket agent and told to board with everyone else.

Luna claims the Virgin employee said pre-boarding for the disabled was discontinued and when an LAX employee spoke up on her behalf the Virgin worker just reiterated what she had said.

A rep for Virgin America chalked the whole thing up to a miscommunication ... they say the airline absolutely offers pre-boarding for special needs guests -- which they believe was offered to Cho and Luna, but they curiously apologized nonetheless.

Cho and Luna are calling BS and say they'd take legal action if they had the money to fight a Goliath corporation.