What if I am accused at the bar for bothering a woman?

This one guy wanted to start a fight with me because his girlfriend was making up stories about me and setting me up and saying I touched her inappropriately and hit her and that wasn’t true and I even was trying to stay away from that crazy woman!! How do I handle this situation? Some woman at the bar made up a story about me because she didn’t like me for some reason and was drunk and all her friends and boyfriend believed her!!!!! That was the whole cause of this big biker guy wanting to start a fight with me and didn’t believe me that I wasn’t doing anything!