Lots of questions about 7mo lab
I have a black lab that I adopted 4 months ago. Despite all efforts, she is still not potty trained. My first dog (who is no longer here) was an instant learner and I never had a problem potty training her. However, not only does my lab pee and poo in the house but she does it inside her crate (she only pees in her crate), I am about to replace the carpet because it is beyond any help from a carpet cleaner. She is also very destructive and has ripped up the kitchen floor, practically eaten a small chair and chews on the corners of the walls. She's a real sweetie but I cannot figure out how to stop this madness! My sister and I both adopted puppies at the same time and before my sister moved in a month ago they played together often and now they do all the time so I do not think she is bored, but my sisters dog does not potty in the house. I noticed that my dog even pees in her sleep, not as much but maybe a shot glass amount or a little more. She is always very thirsty and because of the constant peeing I have to monitor her water intake so that I can take her outside before she goes in the house, she literally chugs a whole bowl of water every time I fill it. I read a little about diabetes and I don't want to jump to conclusions but if there is a possibility I want to find out as soon as possible. My last dog died at the age of two and I never found out why despite taking her to a teaching vet at the university when she fell ill and having an autopsy and blood and tissue samples tested after she died. This time around I am being very careful to spot any disease or disorder she might have so that I don't have to see another of my good friends pass. She also has seems to have lost some weight which worries me because she's a healthy eater and I know that I am feeding her the proper amount and have since fed her a little more to see if it would help.
Thanks to any who respond with any tips or advice, I know there's a lot of stuff here but I feel like if I can give enough info then I might receive more help!