A mandibulectomy can be a difficult surgery to recover from. So many variables can make it hard to relay an accurate timeline. Plus we are not doctors with years of medical training and hands on experience. The patients general health, age, their diet, and many other things all play a part in how long recovery will take.

Swelling can take an entire year to completely subside. Its hard to guess at what point the swelling should be reduced at 4 months post surgery. Any time swelling increases months after surgery, the doctor should be notified and the patient checked out. Maybe it could be fluid build up?

Pain unfortunately can be a long term problem. One medicine that worked very well for me was neurontin for nerve pain.

Im sorry you are struggling with your recovery. I know all too well how difficult the recovery form the mandibulectomy can be. Its full of ups and downs and it can get very frustrating when not seeing significant progress. Best wishes with your continued improvements with your recovery.