Yes, a single traumatic event can absolutely cause PTSD. The longevity of how you are feeling makes it possible that you might have PTSD. And,...this being from a single event is the very definition of PTSD versus CPTSD. CPTSD is being defined as a series of events that has occurred, (repeated abuse, etc.) versus a singular event. What I can't tell you is if what you are experiencing is depression, anxiety, PTSD, or any of the other trauma-based diagnoses. That's where a good counselor / therapist / psych doc etc comes in. Mental health providers are exactly like physical health providers - they all get trained in the basics, then they get more training in specialty areas. It might be helpful for you, therefore, to find a provider who specializes in trauma based care. They will be able to help you figure out whether or not you have PTSD, or any of the other trauma based diagnoses, or something else. The label of what you have isn't the most important thing. How to help you get better is what is important. I am so sorry you have suffered for so many years. Take comfort in knowing that life doesn't have to be as it is now for you. It is possible to move on, to get better, to have a new, good, loving relationship. Sounds like you are heading in the right direction; keep walking. You can find your answers, and find a better, fuller, more meaningful life. A good mental health provider can help you get there quicker and easier than trying to do it all alone.