Is it normal i can only fight physically not verbally?

Learn from other people who use words to manage a situation. IIN is a great place to observe how people deal with conflict verbally because none of us here have the option to hit each other.

You don't need to be some wordy genius (that usually pisses people off anyway). All you need to learn is the techniques people use. Then you can apply them in your own way and with your own style.

You don't necessarily have to fight. But reason with them instead. But if you can't then maybe if you ignore her, she will get bored and move on...eventually

I wouldn't move down to their level, that doesn't accomplish anything, just be careful.

I hope you can sort this out! I mean, I've never really had this sort of problem. I just talk my way out. Although, putting assault charges etc... aside, beating up someone you hate (defensively) sounds like a lot of fun.

Just be... really understanding. and when i say understanding i mean it in a sarcastic/petty/embarrassing/condescending tone. It'll either embarrass her or bore her, and never let her finish a sentence.

I don't know what it is she says to you, so i don't know how to reply, so i'm not sure if these will help but here are a few comebacks i've heard/used in the past. like for example you should open your door/ or call through it when she knocks on it and say something like:
--------------------------------
I understand your retardation and OCD tendencies, but could you refrain from your continuous knocking?
- when she starts to speak, baby her, like saying 'there, there, i know, it's ok, we all have our issues, your's is just more pronounced' etc
--------------------------------
Did they let you out of your room again? The special ward really needs to stop doing that. I see you're still don't have the ability to live amongst the general public.
- if she comments/ tries to insult you.
reply something like Dammit *whatever her name is* are you off your meds too? come on, how are you going to control these anger bursts if you don't take them.
-if she tries to speak again cut her off saying 'Nope, not even gonna speak to you until you take them' and walk away.
---------------------------------
I know you are desperate for attention, you were probably left all my yourself because your parents couldn't find it in themselves to love you... *act dramatic parts to your story like: 'and they only kept you cause they knew it would look bad to throw you in the bin like you so rightly deserve' etc* and then end it with and i know you try to make yourself feel superior. i understand, but you're annoying so go away.
-----------------------------
I know you were frustrated with my reply the other day, but I'm sorry but i'm just not that into you. So you can stop this charade already.
- if she asks you what you're talking about
whisper loudly *especially if she's with her friends* when you ... you know... asked me out.
- and when she starts to deny, or say something catty like 'you wish'
just reply: it's cool that you want to pretend it never happened i feel the same too. so could you stop harrassing me cause it isn't going to make me like you any better.
----------------------
Try to always address her as 'My little stalker'
-and if she asks you how is she a stalker
reply something like: well your always knocking on my door and trying to be around me.
--------------------------
or every time she starts speak: (remember objective is to never let her finish her sentence)

shhh her, or make a noise, or put your hand up, or act like you're about to be sick (when i use this i'm always like "i'd reply but the stench of your breath is making me- *vomit noises*" etc.) and make sure you walk closer and closer to her and you dry heave. if she pushes you away it's go time (because now it's self defense in the eyes of the law).
---------------------------

if you don't care about her finding you creepy:

open your door and just stare at her, if she's smirking shuffle towards her until she has to physical step back. then turn around go back into your room.
---------------------------
Pull out one of her hairs, and maliciously laugh, then go back into your room.
---------------------------
mimic her but instead of a squeaky voice use a deep man voice (if she comments that she doesn't sound like that) just reply that she does and you'd have drawn on a mustache like the one on her face, but you don't like you have enough ink in your pen.
----------------------------

These sound childish, but sometimes you gotta get down to their level.

Use the system report the behaviour to the administration. Once you attack one of these pieces of shit they will see you as violent.

I fight both physically and verbally often, and with decent skill.

Learn some debating skills.

Have you ever heard of a movie called "thank you for smoking"? The premise is that if you are good enough at arguing and do it correctly, you are never wrong no matter what the topic.

Just start acting really creepy around them, make them think you're gonna release some voo doo shit on their asses. When they say something to you, dump some black powder substance onto the floor out of one of those fancy little baggies while you're looking all pissed. They'll leave you alone.

have you tried kissing her? As weird as it may sound sometimes people pick on the people they like.

There was this girl that liked me in the past and she was such a bitch to me later i was told she liked me i couldn't stand her at that point.

You should give her a fright. Don't hurt the poor thing. We do with what we have.