Help................?

k ppl i really need some help..and i kinda need it a lil fast...see the thing is i know this guy...( WE AREN'T GOING OUT OR ANYTHING) jus friends i think.....i liked him as a friend..and we used to get along pretty well...well that was untill i got to know who exactly he was...a lott of people have told me that he isn't nice at all..and i shouldn't be having any contact with him..sort of like a bad guy..a play boy type...other than all this i've heard a lotta other ****..that he bluffs a lot..now i jus don't know what to do...i jus can't seem to believe whatever he says...and want to break things of.. i tried to avoid him, fought with him tell him to forget everything..but apparently he doesn't want to loose a friend..which is **** of course...i want to get outta this thing but am not able to....can anyone pls help me out here..i'm desperate to find a way out...