Man in need

my girlfriend friend said I kiss her and it not true but my girl all upset and depressed about it not knowing what to believe her friend lied and now I have to found a way to prove it or I mite lose my girl

Get this friend and your girlfriend together and talk about it. Tell your girlfriend her friend is lying and ask this friend infront of your girlfriend why she is making these accusations? keep at her so she cracks and tell the truth, find out when exactly she is saying this happend and what happened but you have to be smart about it so she may over step her own lies.