As a former medical student, we were taught it was our job to address all health complaints, including dianosis of things the patient may not want to hear.

Obesity has major health complications. Diabetes, hypertension, stroke, etc. A patient may not want to hear it, but the doctor has an obligation to work in the patient's best interests.

You're sadly mistaken if you think your doctor's only job is to tell you what you want to hear.