This is not so uncommon behavior in some dogs, especially in the circumstances you describe.
Introducing a new dog to the family.
It sounds like it could be an objection to both the interloper (new dog) and you leaving the house. She is a, relatively, old dog and is used to her routines and the household, from what you say was static for much of her life. Dog's are susceptible to changes within the household and can become jealous, if there is a perceived shift in attention away from them to someone else in the household (other pets, children sometimes).
Without knowing clearly the timeframe of when this behavior started with reference to when you introduced the new dog (eg [x] weeks after we got the other dog
, I can only answer generally. If you have been going out more frequently than usual, this could exacerbate the behavior.
How dogs communicate.
Dogs can't speak to us, so the only way she can show her frustration is using her body. So dogs will communicate in ways, we sometimes perceive as difficult behavior: excessive barking, digging, biting, growling, soiling in the home, jumping up to name a few.
In the fuss and natural concern to introduce a new dog to the family, she may be receiving less attention. Well at the very least she was the only dog for some months and she adapted to having no competition for attention.
The gentle solution.
This is the time to give her more attention. When you come home be so happy to see her, use lots of verbal praise and physical affection. It is best to ignore the furniture. There really is no value in scolding a dog, after the fact. Whether or not the dog can make the association with the act, it serves no purpose to further isolate her, by scolding her. (When I say isolate, I am speaking from her point of view, I don't mean to say for an instant she is socially isolated.)
Take time out each day to spend some time with her and let her know she is your special girl. Treat her, play with her, walk her, I would recommend giving her some one on one time to begin with, as she may be feeling a little insecure. Your previous dog died and was replaced. Dogs are not as silly as we may think. (my opinion).
Gradually you can mix the new dog in with this special time, so she associates the new dog with attention from you, treats and fun.
Separation anxiety.
If the problem persists, I would suggest that it could be separation anxiety, which is another issue. Given the details you have provided, I think the extra attention and time with her, would be the best way to go.
As a side note, you do not want to be held ransom by your pet, but if you are able to temporarily increase the time spent at home with your dog and gradually increase your time away, combined with the above techniques, this may assist in alleviating the problem.