I'm a man who witnessed a bunch of guys harassment a woman on the street

I was walking home from work at 3pm when I saw 5 guys following this woman while yelling and cat calling at her. I was about 10 feet away from them and saw her look at me with pleading eyes for help. I kept walking. I felt bad but I really thought the best decision was to just keep walking. I don't know what would have happened if I would have tried to help her. I just hope she's okay