I am a firm believer that proper nutrition can overcome all three but you do need mind over matter as suggested below. First believe you will find the right path, look for it, give your body what it needs to think clearly and with proper perspective. Plenty of brain food.
Depression, stress and anxiety? What are my thoughts. Mind over matter. You don't mind, it don't matter.
Depression- Yes, I've suffered from it in the past. Was able to overpower it with my will power and understanding- Depression is mainly one's own view. One's inability to change one's own view will lead to one being depressed.(aside from any chemical imbalances, which in theory could correct itself, since the human body has the ability within itself to heal)
Stress- Yes, I've suffered from it also in the past. Again, sheer will power to overcome and understanding- Stress is related to own actions, knowledge and experienced gained, and how it is specifically used. If one lacks the ability to utilize actions, knowledge and experienced gained, then stress will likely mount. Until, breaking point.
Anxiety- Yes, I've suffered from it too. Again, sheer will power and understanding- Anxiety is an overwhelming feeling many suffer from. It comes in too many forms and must be dealt within every situation or circumstance it arrives at. This defaults to actions, knowledge and experience gained. If utilized properly, anxiety will be a short term, intermediate problem at best. If not, then it seizes the individual, so as to create a panic attack, in most cases.