If she is unreliable in the house she should never be anywhere where you can't see her. Until you are sure she is trustworthy she should always be in the same room with you on leash. This will be crucial for you to start re-building the house training.
If she is only messing when she is out of your sight it is because she has learned that it is rewarding to go in the house - as long as no one is looking. If you are punishing her for having accidents I would stop. Unless you catch her in the act the she will have no idea why she is being punished, and if you punish her for peeing/pooing in front of you she will only continue to do what she is already doing - make sure you don't see. When you do catch her having an accident you need to interrupt her. Clap once or twice and say "oops" or "outside" (loud enough to get her attention but not frighten her) and immediately lead her outside. Praise and reward heavily when she finishes.
Start taking her out for regular toilets and praise/treat her the second she's done. You may want to add in a game like fetch afterwards to increase the reward of successful elimination and to deal with some of the excess energy.
If she is never allowed to successfully eliminate in the house this behavior will extinguish itself.
Keeping her with you will also help you curb the chewing behavior. Start measuring out the food she would normally get in a day and put it into puzzle toys (kongs etc.) to engage her mind. Put something really smelly and delicious in the bottom, like wet food, to keep her interested. When you see her try to chew on something you don't want, re-direct her to one of her toys . You then need to make that object less desirable for her to chew in future. You can pick up a bitter spray from your local pet store - when her attention is diverted, spray the area thoroughly. This should make it a lot less rewarding
I know it seems like a lot but this will really help if done properly, and it's not for forever.
Let us know how it goes
(Oh, and make sure you are using with an enzymatic cleaner for her mess to de-nature the urine/fecal smell)