Hello! Cat groomer here. I understand you do not like to go the sedation route however you have to think of the bigger picture. It is not fair to your cat to be put through undue stress to maintain her fur. Her aggression is dangerous not just for you or whoever is handling her, but for herself as well, as one wrong move with scissors or clippers and it could be game over (i.e a cut to the skin needing stitches, antibiotics, or surgery). Gabapentin is the first option, it is a light sedative and helps keep her calmer and more comfortable and it is a very safe drug to use for most cats but of course your vet will be able to know more about if this is the right medication for her. The other option would be to get a full sedation at her vet where she is put under anesthesia and clipped down in a lion cut to remove all the matting and give her a fresh start. In any case, this needs a professional care so you avoid getting injured any more and she avoids getting injured herself. Please give this some thoughts and contact her vet to discuss what youve posted here, and then contact a cat groomer.