Weed doesn't cure depression

I said "manage symptoms" not cure. Better to have depression under control so you can work on treating the root cause then sitting in bed.

You can treat depression through natural means like diet, exercise, Vitamin D, and socialization.

Weed is natural, not that natural necessarily means good. Some depressed people undereat, and weed helps their diet that way. I used weed to make nutritious foods taste better.

As for socializing, that can be hard for many depressed people, but smoking weed makes it much easier to find others to hang out with. In my experience, I can bond with someone who smokes much easier, even if we have very little in common otherwise.

A broken leg does not work the same way. You are comparing a physical need to a psychological one.

The brain doesn't exist outside physics. Weed, just like pharmaceuticals, interacts biochemically with your brain.