Oh poor you. I lived through this with Cora ten years ago.
She had been rescued from a clan of 20+ cats who had been allowed to breed unchecked in a house with uncaring owners, so by the time the RSPCA got involved most of them were set in their ways - unsocialised and almost feral.
She was 1 year old when I took her in, a beautiful, dainty tabby girl, so loving and playful. I kept Cora for 10 months in which time she bullied poor gentle Beau into a quivering wreck and trashed my home - her wee was up every surface, the doors were splitting and my kitchen cupboards boards burst, the floor was soaked through to the rafters, all my clothes stank of pee and I just couldn't cope with her any more.
She would use the entire house as her litter tray, and although she had free access to the outside and fresh litter daily, she wouldn't stop.
I spoke to the RSPCA who agreed that she was out of (my) control and maybe she needed to be re-homed as an "only" pet.
I cried when I left her there. The hardest decision I ever made. I felt like I'd failed both Cora and myself. But once I'd cleaned out the house, got new carpets and re-decorated, suddenly life was once again good for me and Beau. He came out of the airing cupboard and I could have a day off without spending all my free time scrubbing and cursing.
Cora, I heard later, was re-homed to a lady with no other pets, and was much happier being an indoor cat. It seemingly was the prior presence of poor Beau in "her" house (even though he never marked or sprayed) and she just couldn't help herself.
So, over to you.
The stress she's causing you will certainly be felt by her and may even be making things worse. She may resent the dog, or the attention you give him, or maybe she's just got set in her ways. Whatever it is, try not to get angry with her, or yourself for that matter, it only serves to make matters worse.
There are new products for cleaning your place and helping your cat that were'nt around when I had Cora.
Try RX66 from Xeria
http://www.livingiseasy.co.uk/search/?search=rx66for old pee stains on upholstered furniture and wooden flooring, which really does work if you follow the instructions to the letter. Be generous.
For general cleaning I have a gallon of Simple Solution (Pets at Home have this if you want some today).
http://www.amazon.co.uk/SIMPLE-SOLUTION-REMOVER-LARGER-LITRES/dp/B004B3IQAI/ref=sr_1_8?ie=UTF8&qid=1317472592&sr=8-8which acts in a similar way but is slightly cheaper for everyday cleaning and de-ponging litter trays etc. Decant some into a spray bottle.
Where she is peeing up wallpaper, use a boot waterproofing spray to create a non-absorbent barrier white newspapers below to catch the wetness.
Puppy pads placed on your settee, covered with a throw so your neighbours don't think you're incontinent, will help protect that. Wrap cling film around the bottoms of your radiators and wooden doors to protect them. Restrict the rooms she has access to to save yourself some work.
Try a Feliway plug-in too, and some Rescue Remedy or Zylkene for her, she may respond well.
Ask your vet about Buspirone, which has had good success in controlling spraying behaviour in cats.
I really do feel for you, but there are a few things you can try yet. There will be plenty of folk on here who have great advice, read through the old threads in Health and Behaviour section that look appropriate, and Good luck.
