She is bonding with you. It is good that she is calm - means she isn't worried until you are out of sight, then she will follow as she is devoted to you. If you don't want her on the settee, you must stop her NOW as it isn't fair to allow it now then stop her later. SBT's aren't "barky" dogs in my experience. They have a little squeek when they want attention, unless they need to warn you of something, then they bark. She is eating well and walking well, if her poo is ok too then all is well. Congrats on getting a rescue dog and extra brownie points for getting an older SBT by the way!