put in writing that you are unable to work with this person on the grounds that she talks loudly and is rude to you when you are out of the office, that she is a different person in the office and that you do not trust her because she shows two such different personalities when with you depending on whether you are alone with her or in the office. also in the letter request to be transferred to a different social worker...not your old one as that is likely not to be an option, but another one is a plausable more likely option. address the envelope to the head of the office/ manager of the office, personally hand the in to them or the reception.

social work bosses have to take notice if A..you put it in writing and B...you state you feel you can't work with this person...after all you need to be able to work with your social worker to enable you to get well/keep well.

good luck x
until then whenever you get in your social workers car say 'i would prefer not to have music playing in the car as it really upsets me' if she refuses to turn it off refuse to get in next time and request a different person collects you or say you will make your own way there and meet her there. otherwise try having a friend or someone else with you ...they can't refuse you having someone with you after all you are a 'vulnerable' person in their eyes!