We rescued a 10 month old female boxer. We have had her for 2 mo. and she is still peeing in the house and chewing on EVERYTHING. She ruined my couch, blinds, an expensive rug and lots more. We never experienced this with our 8 yr. old male. We need help!
Are you crate training her? This could help tremendously; keep to a regular schedule of eliminating, regular food & water, and crating overnight & for periods of time during the day.
Get a crate that is big enough for her to move around put it by the door. When you get up in the morning take her out and then take her out every hour after that for a couple days and then slack back to every couple hours giving her some kind of treat when she goes to the bathroom like milkybones, a steak bite, or something like that. It shouldnt take more than a couple of days to break her of the habit. She should be letting you know either by barking, walking around the house sniffing for a spot, or going to the door. Just got to watch her and she will let you know!! Good luck!!
You should have been in training with your pup as soon as you got home with her, it is never too late though. Best thing I ever did was take my guys to puppy school. Ask your vet to recomend one to you.
You need to start over and treat her as you would an 8 week old puppy. Crate train her and do not let her roam the house unsupervised! It will take a little work esp. if she has never been in a crate but it will be so worth it! Get a good book on training boxers. Stick with it and good luck. If you are consistent she will get it and turn out to be a great dog. It is so much easier to prevent the behaviors you don't want than to change them later.