Hi there. I live with an old woman who sometimes pockets some money to work as an informal dogsitter of sorts.
So she got a pretty good amount (half a month's minimum wage where I live) to take care of a removed for a week. She doesn't accept pissfingers, though this is one of the top 2 questionable dogs she ever accepted. An adult female shih tzu with a teeth pointing out (like this picture) which means it probably came from a puppy mill.
This dog took an instant liking to my pensioner, but not to me. Also we're both females of similar stature and the dog's owner is also a female. So it's not man shy.
Whenever I approach this dog, she retreats and hides herself under a table or wardrobe. If I approach her within a range of 3 meters, she gets further away. When my pensioner is home, the dog follows her around like a shadow (expected behavior for a companion dog I think) but also puts herself between me and my pensioner barks at me when I get near. The dog never barks at me when I'm alone with it.
Whenever I open my bedroom's door, she also begins barking. She doesn't stop barking when she sees it is me. The only time she won't do that is when we're both in the kitchen, which is also our dining room, probably because she hopes I'll throw some scraps from my table (which I never did, but my pensioner does even though I told her not to do it).
She also barks back whenever a dog barks in the street. We live on the third floor of an apartment.
The dog is not bite/scratch oriented. The only time I can go near the removed is if both her and my pensioner are cuddled together in the sofa or bed. She either won't bark or ceases barking when I sit down in the sofa, but still keeps looking at me like I'm a convicted criminal. She allows herself to be pet, but is visibly uncomfortable when I try to do so, even when I don't pass my hand over her head.
Probably the worst thing though is that she has a piss mat. She usually knows how to use the piss mat, but when no one is looking she will pee in front of my bedroom's door (which is always closed). Our floor is carpeted.
Things I have tried so far that didn't work: Talk to the dog in a "toddler" tone, squat to talk to the dog, lay on the floor to talk to the dog, share space sitting next the dog, pet the dog and then give her some kibble (she wouldn't eat from my hand), put the kibble in front of her and retreat my hand (she would burrow it within the blanket instead of eating), live normally not paying attention to the dog whatsoever.
Dog also really dislikes going out for a walk and hides before being collared.
I'm thinking in buying some treats on a pet store and try the kibble strategy again but with something tastier.
When my pensioner is home, the dog follows her around like a shadow (expected behavior for a companion dog I think) but also puts herself between me and my pensioner barks at me when I get near. The dog never barks at me when I’m alone with it.
Just an idea: A dog following around often is a controlling behavior which insecure dogs do and barking at you could mean: "This person is my person to control, stay away!"
Sitting on the sofa basically attached to a person is the maximum of control the dog can have (can only be stronger when the dog puts its head onto that person to basically pin them down), so maybe you are not that much of a threat in this situation but still not welcome on the sofa.
Peeing is marking territory, which can mean she barks at you when you go to your place saying: "Yeah, leave to your place, don't come back!" and peeing means "This is the border between our spaces, you stay better out in your place, I marked mine/ours!"
Barking at street dogs can also be a "Stay out stranger dog!"
Not wanting to go outside to a place that the dog can not control as good as the house would fit too, since the root would be the dog beeing very insecure.
If the dog is new to your house it could get settled in and the behavior could go away, or stay because it is routine after a while.
If your pensioner would be in with that, you could start to change the following behavior, so that the dog learns constant controlling isn't worth it anymore. That would mean there is no need to defend its position as "master controller" anymore and could allow for a better relationship between you and the dog. A more relaxed dog could lead to less avoidance to go on a walk.
All of this might or might not at all fit for the dog and your situation, I am just trying to compare it with a dog I know who had similar reactions to a second person living in a flat. It was a terrier though, but we were able to solve the problem.
Still the dog had a favorite human but the other person became an accepted member of the family and they were graciously granted the right to pet, feed and accompany on walks when the favorite person wasn't available. :D
I hope you will find a solution that fits all three of you!
If your pensioner would be in with that, you could start to change the following behavior, so that the dog learns constant controlling isn’t worth it anymore. That would mean there is no need to defend its position as “master controller” anymore and could allow for a better relationship between you and the dog.
How?
Thanks for saying it's a territorial dog, knowing this is already half the road to success.
The person "controlled" by the dog began to behave completely irrationally.
Ignoring the dog completely, they would get up from the couch, walk to a room, turn around in the middle, walk into a different room, close the door behind them before the dog could enter (sometimes I would help to distract the dog so this could happen), but they would never stay in the room for too long (we started with one minute and then the time frame got longer and longer, sometimes making noise in the other room, sometimes not), get off the couch, walk to the kitchen table, sit down at the table, get up after a few minutes, walk out the front door, get back in after three minutes, and so on and so forth. The dog is put down from the sofa every time he tries to get up and prevented from getting up again, and especially from putting his head onto his favorite person when they are sitting or lying down somewhere.
You can trick the dog by getting your coat but going to the kitchen instead of out of the front door, getting your car keys but not leaving the house... whatever habit you have, just break it, it is even more effective if other people in the household join in and if you have visitors who do it too and all of you being relaxed and into what you are doing.
If the dog starts to scratch at the closed door, open it and stand straight up looking down on the dog and sent them back with a hand sign, demonstrating "I don't need you right now, back up!"
Show only affection to the dog inbetween by calling its name, petting it, etc. preferable in the same space, like when you are relaxing on the couch and the dog sits before you. Ignore the dog the moment you get up. So the dog learns to read when it is "being close together time" and when not.
It took us a full week, doing it every day for some time. At first the dog was irritated and there was a bit of frustrated peeing on the floor and chewing on a sandal (we monitored the behavior to not get the dog too stressed out), then he got more and more bored because it didn't make any sense (I mean, he wasn't wrong) but it didn't hurt him and he realised he was still safe and finally he gave up and layed down on his blanket with a look on his face that still makes me laugh: "Look what I have to put up with!"
We made sure he had a place (his blanket) in the living room where he could still see a lot of what was going on in the flat, so he did not feel left out.
He tried to revert to this behaviour a few times after that, especially after a visit to the vet, which he hated. But as soon as the irrational behaviour started again, he remembered that his humans were uncontrollable and stopped.
We did not come up with this on our own. We watched a dog trainer do this on a video and tried it ourselfs. I am sure there are videos about this or similar ways to do it out there.
I am not sure this will work with every dog just the same. If your dog reacts extremely stressed you might have to vary and test out what works for her, maybe limit the time you do it and accept it will take a longer time to work. The end goal has to be a relaxed dog that trusts you to find your way alone and doesn't feel it's their job to keep herself and her favorite person safe.
Perhaps show more affection towards your flatmate? I mean, I'm not saying you treat her like shit. But perhaps the dog needs to know you're not a threat to her? Bring her food or something, I dunno.
I didn't know what a pissfingers was, so I looked it up.
Here it is for anyone else who doesn't know:
Pissfingers is an online slang term for an old dog with highly specific medical needs or, more infrequently, dogs that are particularly difficult to care for, such as those having past traumatic experiences or bad behavior. source