Sounds like you're doing the right thing. Harassment is harassment and trespassing is trespassing. So if either of these things are going on, go to the police or call them. You never know, the whole buying a plane ticket coulda been made up to test your reaction. But its likely not. Do whatever you have to to stay safe, up to and including calling the police if you need to. Just decide all this BEFORE hand. in the moment, our thinking gets skewed.
good luck