MIL Harassment

So me and SO have been falling out and lately his mother been texting me non stop and I’m the past she has told me if I don’t answer her phone calls or texts she is going to come to my apartment. I have a 9 month old and I am currently pregnant ( 6 months) I know she isn’t all there at all . Tonight she said the same thing and I told her twice to stop contacting me . Can I press charges on her? I don’t feel safe her knowing where I live and I can’t afford to move out just yet .