I'm sorry to hear your poor dog is going through this.
This info might help :
There is a limited amount of ways in which you can deal with a phantom pregnancy that is already underway, and the condition will usually go away on its own as your bitch’s hormone levels change and return to normal. However, a bitch that has undergone one phantom pregnancy is exponentially more likely to go through the same process again with future seasons, and as bitches come into season once or twice a year and the phantom pregnancy may run on a lot longer, this can prove to be a recurring problem for dog and owner.
Spaying the bitch will of course resolve the problem, and if you are not intending to use your bitch for breeding, there is of course no good reason not to have her spayed as early as possible! One of the main problems of a phantom pregnancy can be milk production, which can be fairly copious. Your bitch may lick her nipples, which will stimulate milk production and increase hormone levels too, so preventing your bitch from doing this by means of a buster collar or putting your bitch in a t-shirt may help to shorten the length of the phantom pregnancy.
If the phantom pregnancy goes on for a long time or is particularly problematic, your vet may recommend a hormonal treatment to dry up her milk production and counteract the effect of the female hormones that are leading to the generation of the false pregnancy symptoms.
Phantom pregnancies are not physically harmful to your bitch but they can lead to emotional changes for the duration, so it is important to work closely with your vet to ascertain the best course of action to follow.
I've bred and shown dogs all my life and only ever experienced this once, so it's not the norm. Not that that helps but it does pass