OH poor baby! You must be devastated
Let me ask, how did she break it, what part of the leg, and how severe is it?
Most dogs heal quite nicely, even with nasty fractures, but after care is vital in proper healing. Without knowing the details it's very hard to say what you can expect. Simple closed (set without surgery) reductions are much easier to care for than compound open (set with surgery and/or pins/plates) reductions. There will be a period of adjustment for your dog due to casting and limited or no use of that limb, but it usually only takes a few days. After that, you want to make sure that the pup doesn't do anything too strenuous like running, jumping, or wrestling (playing rough) because you don't want any additional damage done. Another thing you might want to avoid is excessive pain control drugs. A little pain is a good way for the dog to self-regulate it's activity. To much medication can encourage activity or excessive sedation, both of which have their drawbacks. To much sedation can cause a lack of exercise which is necessary to maintain muscle tone and strength. Little to no pain can give the dog a false sense of physical ability and they may try to do things they shouldn't.
Antibiotics are very important in the treatment of fractures to prevent infection. Infection can cause a prolonged healing or prevent the fracture from healing altogether. Severe infections from fractures can also spread throughout the whole body and the animal can become septic (infection of the blood) and that can be fatal. Make sure to give all antibiotics and at the proper intervals. IF for some reason you dog becomes very lathargic, goes off feed and water, or starts vomiting, a vet visit is in order ASAP.
I'm sure that your vet will go over all of this with you and s/he knows what is the best course of treatment and therapy for your dog. Keep in mind that these things do take time to heal, so you will have to be patient and be prepared to help your dog (initially) with it's "business" duties, carrying it outside, upstairs, etc.
Good luck with your baby and keep us posted. My gang and I are sending healing thoughts and prayers your way

Glad to have you on the forum.