Was it a vet with experience in snakes and reptiles?
This part:
If she's lost 130g from 400g to 270g and can't eat anything more than a mouse hopper without regurging or bleeding, there is something wrong. Your vet may not have found it for one reason or another (possibly inexperience with reptiles) but I would say your snake is in need of a visit to an experienced herp vet.
How many times has she regurged in the last two or three months (or whenever the troubles started)?