(저를) 떠나지 마세요. if you say this to someone older than you or who you think deserves to be respected, use this sentence (with or without the object in the sentence, '저를'.)
(나를 or 날) 떠나지 마. if you say it to your boyfriend or friends, u can use this sentence.
the sentence given by noah means "leave me in various ways or for diverse reasons."