I would start by bringing a clean urine sample in to your veterinarian to have it checked. If there is an infection pets will tend to have accidents. If the urine is normal then there could be an emotional component involved. If that is the case I would give ANXIETREX. In either case I would give probiotics since it can positively influence UTI and behavior.
Be sure to treat any soiled ares with enzymatic odor eliminator to destroy the odor molecules so that she will not go back to the sames areas again and urinate.
Please let us know what you find out.