I think the most important thing is that if you are hearing from the police about her fear of harassment, STAY AWAY FROM HER. Otherwise, you are likely to be arrested. (Whether you are really doing anything wrong or not.)
If she says that things are over, you really should believe her. It is possible that she will change her mind, but for now, it sounds like she means it.
Even if she does change her mind - which can happen - you still need to "STAY AWAY FROM HER". She just gave you a legal "shot across the bow". That's a nautical phrase from centuries past, still used today, to warn/stop the other ship.
Of course, you didn't harass. But harassment is a very strong legal term, very nearly to the level of DV or abuse. If she is invoking this, you must listen and heed accordingly. Don't play with fire, she's got her fire already lit, metaphorically speaking.
She involved the police. This is big time. Once the police get involved you have to listen. Yes, nothing may come of this, the police are hoping this ends the matter. Even if she doesn't follow through this time, this is a heads-up to you that there very well can be a Next Time and Next Time could be much worse. Listen. Listen Hard.
Looking back, what triggered this? She probably overreacted when you emailed her stating, "I know you are afraid and sabotaged our relationship so I wont like you... . " Perhaps that's all she saw, her disordered perceptions didn't register the next part, "I forgive you." Or maybe she did and the email still felt like an accusation. Your email sounded to her like it was her fault. So she overreacted and decided to use the system against you. BPD is a disorder where fault is never perceived as theirs, so she had to shift the blame elsewhere and thus she blamed you and emphasized it by calling the police. She just had to make you the one at fault - or at least look worse than her.
I am feeling like a complete mess... . cant stop thinking about her and how she has devastated my world... .
It is often said that recovery is a process, not an event. Give yourself time to recover. While peer support such as here is so helpful, have you considered seeing a counselor or therapist as well?
Remember, if you're seeking 'closure' where she admits her part in the relationship's failure, you won't get it from her. Closure will have to be something you gift yourself. Then Let Go and Move On.
