Friends bf stole money from her?

My friends ex bf stole money from her a few months ago and they stopped talking/broke up etc...however, lately they have been kinda running into each others paths a lot..and when she sees him..she doesn't go near where he is...like she hangs out with his sis sometimes ..and if she runs into him, she'll back away or try to hide/avoid him. Why is she doing this? she didn't steal from him...he stole from her....she shouldn't be the one avoiding him..but she seems to be doing so. She hasn't said a word to him either.