Friend or Enemy?

Story Time: I've been friends with this girl for 5 years. Her bf of 3 years just broke up with her. I've met the guy one time. Well that was a year ago when I went to help her out at her house. And he came over. They went to her room and did their thing while I was working on other stuff. She texted me and said that the I was the reason he ended it with her. He wanted to have a threesome. And she was mad at me for not doing it. #1 I didnt know that he wanted that #2 would not have done it anyway beacuse I was in a relationship. How is she gonna say that I was the reason the broke up now over something that happened a year ago. Should I stop talking to her to avoid any more drama that may be spread?