Sexual harassment in public transport - we need to talk about this

Yesterday on the metro a man touched me inappropriately. When I confronted him loudly he said I was imagining things. Other passengers looked away. No one helped. I felt so alone and violated. I reported it to the security but they seemed uninterested. This is not the first time. Almost every woman I know has similar stories. We cannot keep accepting this as normal. I am sharing because I need to know I am not alone and because staying silent protects the harassers. What can we do to make public spaces safer? Has anyone had success with reporting these incidents?