Feeling terrible again after a year. What should I do?

Ex boyfriend started a smear campaign after I broke up with him because he was treating me badly - to see if he would change. He spread nasty rumors about me to people I don’t even know. A year has past by and I still feel like a stranger in my own town. I went into a shop today, not realizing that it was owned by one of my ex’s friends. As soon as I starting looking at the clothes I started to feel so uncomfortable, the sales people were looking at me so badly basically letting me know I was unwelcome (like the scene in pretty woman). I felt so uncomfortable and sad. I don’t know what to do anymore but it’s getting hard to bare