Depression Support Group
Depression is a real and debilitating condition that is often misunderstood by family and friends. Its meaning can range from a prolonged period of sadness to an actual mental illness with specific symptoms. Find and share experiences with others who are going through the same struggles.

You've been through a trauma and it takes quite a while to work through trauma's before you can get to the other side where just the thought or remembrance of it doesn't cancel out all of the healing you've done. You need to be working with a Therapist to help you deal with the Trauma and work through those feelings, it's the only way you can get through it and back to some semblance of normalcy.
Regarding those who don't believe you, there's not much you can do about that, and you need to focus on you and getting better, not what others think. Work with your Pdoc, and work with your Therapists so that you can get through this and the depression.