Hi all. I don't know where else to turn except to other loving dog owners like myself. I will start from the beginning. I have a 12 year old Toy Poodle named BB. She is a wonderful pet whom I love as a child. My boyfriend even picks on me about how much I do care for this animal. BB was given to me about 5 years ago. I know that before I got her she had been mistreated by someone who used a belt. To this day if you have on a belt and you simply take it off and she sees it, she will bark agressivley. If you show any violence in front of her such as adults or children hitting one another she will bark in the same manner. That is the only time she will show any aggressive behavior. She has never bit anyone for anything. I got a cat over a year ago. She was completely fine and had no changes in her attitude or anything towards the cat. In fact they even sleep next to one another and I have seen her licking the cat as in maybe like a motherly manner. They even sleep under my bed together at times. The bed is BB's primary dwelling place.
Now here is where it gets strange. Within the last 2 months BB has gotten really really bad at peeing in the kitchen floor...everynight. I can take her out as late at 1 or 2 am and by 7 am she has peed on the floor. I scold her and she will run and hide under the bed. When I finally had had a enough of cleaning up after her I took her to the vet. She stayed overnight at the vet so they could do blood work/urinalysis and other exams on her. The vet said he thought it might be cystitis and the crystals that are forming in her bladder. So he sent her home with some antibiotics and some special dog food that is to help dissolve those crystals to keep them from becoming larger bladder stones. The vet also seemed to think it could be psychological that she is doing this or it is mere habit that she is peeing in the kitchen only at night. BB and the cat are left home during the day alone and she never has accidents during the day. Why would she only do it at night? And it's usually in the same area.
Next strange thing, as mentioned before BB is a sweet loving non-aggressive dog. Listens well and knows when she is in trouble. Well ever since I brought her home from her trip to the vet she has started acting very skiddish and scared. She seems to be very afraid of my boyfriend as if he has done something to her...but he has not. She would follow me around wherever I went in the house. She would literally beg to lay in the bed with me. So I would let her. I left to go to the store and she preceeded to follow my boyfriend to the bathroom. He was fixing to take a shower when he bent down to pick her up(she was hiding/cowering between tub and toilet) SHE BIT HIM. Drew blood and everything. As stated before BB has never bit anyone. I just do not understand her actions now. When I came back from the store it was back to being up under me. My boyfriend feels bad that she doesnt want anything to do with him and feels like he has done something wrong when in fact he has not. She had no problems with him before. He tried to make amends with her by feeding her and loving her but she didn't want any of it.
The next strange incident, after the boyfriend left to go to work, BB wanted nothing to do with me anymore. She layed in her chair all night. She seems depressed now. I called her to get in bed with me because I know she loves to snuggle and sleep next to me but she did not stay there. She got back off the bed and got back in her chair. Which is where I found her this morning. She was not under the bed like usual. When I went up to her to try to pet her and tell her good morning like I usually do she snipped at me just a little and tried to turn away from me.
All of this is very strange behavior for her. I have NEVER EVER seen her act like this. It's like she's mad, depressed, and scared all in one. If you have any ideas please share them. Please help!!!

I think you need a second opinion from another vet. This could all be connected to a physical problem. At 12 years of age your dog is a senior citizen, and just like all seniors, things start going wrong. She could have a kidney or liver problem, arthritis, diabetes, failing vision, or geriatric cognitive dysfunction, just to name a few.

I would like to add to the situation about BB. Last night when I cam home from work my boyfriend was with me and I sort of expected BB to greet me just as she always does...but she did not. She was immediately acting scared again. She continued to try to stay up under me the entire night following me around, worse than a child I might add. Another strange happening occured when I went to feed her. In the past when I put her food out she would wait till I was done and had walked away from her bowl. She would even then sometimes wait till she could not see me anymore before starting to eat. But not last night, she was there eating before I could even finish dipping it out into her bowl. She has NEVER been like that. I feed her wet food but keep dry food out at all times so I really don't think she was THAT hungry. I think it was more like she was afraid I was going to take it away or something. And now she has stopped eating her treats. She will take them from me but she just drops them on the floor and looks back up at me where as she used to almost snatch it from me and run away with it to eat in her favortie spot...under the bed! And to make matters worse, last night, as my boyfriend continued to try to be sweet to her by petting her and rubbing her belly(something she USED to love) she started to snap at him. She did this several times. At first we thought she may be sore or in pain or something but when I did the same thing she never snapped at me but still seemed not to enjoy the petting. This is all getting very upseting to me. I don't know what to do and I don't want my dog to continue to act like this. This is not the BB that I love dearly. I am now afraid to bring her around my boyfriend's 2 year old son for fear that she may snap or bite him.
As vetgroomer mentioned, it could be something more physical, I would just like to reiterate that she had complete blood work and urinalysis done so I feel that if it was somthing with her liver or kidneys her CBC would have come back abnormal. I can't help but wonder now if the amoxicillin is causing her to react this way, even though I seriously doubt it. I wonder if she thinks my boyfriend is going to hurt her because he is a male and there was a male that treated her at the vet.
Please help. Please give advice if you have any that may help. I'm getting desperate! Thanks.

Blood work and UA should have shown if there was something going on with her liver or kidneys, as well as ruling out diabetes. But it won't show things like vision or hearing problems, arthritis, infected teeth, or cognitive dysfunction. Some conditions like Cushing's disease, Addison's disease, and hypothyroidism require specific blood tests. Also, the blood work and UA did reveal one problem; she has crystals in her urine. That points towards the possibility of a beginning kidney problem.

Something is definitely wrong, and you need to follow up until you find out what it is.