Topic: Can a simple event trigger this?

As I explained in another post, I think mine was triggered from a mother who "told me how to feel." If I didn't feel the way SHE thought I should feel, I would be "told" how to feel. Thus, I cannot connect to my emotions at all.

Though I am not a doctor, it would seem to me that alexithymia is strongly related to light forms of asperger and autism and cannot be triggered by a shocking event.
It seems that you describe a sudden lack of joy in life and no pleasure in being with people or doing things you liked before. This would rather point to a form of depression, which may be treated by a psychologist (or pills).

It is also possible to suddenly not feel any negative or unwanted emotions anymore: anxiety, sadness, love for someone else's wife. One feels ashamed of these feelings (men shouldn't cry; I shouldn't be in love). As a coping strategy one can repress these feelings and not allow them in one's consciousness. This looks a lot like alexithymia and even a good professional may not be able to tell the difference. Repression needs psychological treatment if the person is seriously impaired by it, e.g. unable to work normally.

For me the difference seems clear: Alexithymia applies to all emotions. Depression applies mainly to the positive emotions (though I guess depressed people are not very angry, because they are not reactive). Repression applies to unwanted, hence mostly negative emotions. A person having unimpaired capabilities of reading someone else's emotions is less likely to have alexithymia.

From my understanding, it's trauma, injury, or both that can contribute (but not cause) it.

I think mine is a combination of my mother TELLING me how to feel (which is wrong) and the fact that my delivery as a baby was by forceps, my mom said my head collapsed down to my eyes. It popped back out later. I think I had a possible brain injury from this.

Although no expert on this subject I have read of and observed people which display this trait over many years and I believe a single event may cause similar behaviour but like Tjerk I believe in these cases it is a form of depression. I also think very few people with alexithymia can label their own behaviour because to them it is normal and they do not see it as a problem. Which to them I might add it isn't. It only becomes a problem to them when and if the people they relate to have difficulty in accepting their way of thinking and become critical. In such cases they see this as the critics problem and have no qualms about ignoring it.
I believe very few people with alexithymia will post here as I believe they will only recognise the trait when it is brought to their attention under counselling conditions. Even then they will not be emotionally affected and move on with their lives.

For me i think it was growing up in church .My whole life i was told how i was supposed to react and how i was supposed to feel about things, so i never developed my own feelings towards anything.

Judging from what I've read Alexithymia can be manifest both from the result of a traumatic event and also it can simply be a condition that someone is born with. Perhaps even when a traumatic event triggers alexithymia it might already have been an existing condition that simply required a catalyst to bring it to the fore. Autism can be similar, with apparently "normal" children becoming autistic after a severe childhood illness. The illness of itself obviously doesn't cause autism, the condition was already preexisting but the onset of the illness acted as the trigger.