Since constipation seem sto be the main problem, I'll go ahead and give you a first aid measure. You are on the right track with baths, but we can make them better.
Buy some Pedialyte (yes, the kind for human infants), and some prune baby food. Drop a small dollop of the prunes right on the end of her snout. Most of the time, reflexes will cause them to lick it off. Wait about 45 minutes, then prepare a shallow warm bath consisting of 1/2 water and 1/2 Pedialyte. Soak your dragon for about 20 to 30 minutes. After the first 10 minutes, with her still in the water, gently massage her underside from front to vent for an additional 10 minutes. That may be enough to help her pass some feces. Be sure to supervise closely.
The other information may have helped me to figure out an underlying cause. Loose substrates like sand or crushed walnut can lead to constipation in sensitive beardies. Reptile carpet or ceramic tile are better choices. For some dragons, being even a bit too chilly can cause a sluggish digestive system. The basking area should be 105*F to 110*F. The cool side should be 80*F to 85*F.
If this problem has been occurring throughout her life, she may have been born with a genetic defect causing the problem. If that's the case, there won't be anything you can do.
Your dragons do need calcium more often - prey insects should be dusted every day.
If you have more questions, just let me know.