Anxiety and depression have a close relationship and both represent a chemical imbalance in the brain. When you have an issue like this to the point of disorder, it's unlikely to be the only problem. Psychiatric labels like PTSD, GAD, OCD, BPD, serve to categorize the behavioural manifestation of the imbalance.

I don't claim to have a cure for depression. However, meditation has been a significant help in balancing my emotions and achieving calm. I am convinced poor diet and sleep hygiene are major contributors to mood disorders. Work on those in tandem with practicing meditation. If that doesn't work for you after a few weeks, the medication will still be available.