What you saw is definitely very "traumatic" and it is very understandable that it resulted in your struggling with PTSD. It definitely takes time for a person to slowly grieve and process something like this. Your mother may be having some PTSD symptoms too which can be a part of her needing to cling to you. She should be seeing a therapist too. Often what a person can struggle with is "complicated Grief disorder", which is something you can look up and read about, perhaps even share with your mother.
You deserve to have a therapist that actually "knows" how to treat this kind of challenge, the therapist you have described clearly is not capable of treating this kind of challenge.
Here is a link that talks about "Complicated Grief".
http://www.currentpsychiatry.com/hom...988bdd053.html
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