This is the first time that I have seen this thread and the discussion and the comments have been very enlightening. From my own personal perspective, there is a huge difference between faith and religion.
Faith is the personal experience/relationship we have with God, our creator, or whoever or whatever an individual puts into that role. PTSD also impacts our ability to "have" faith, in that faith requires trust; and there are also areas of the brain that suffer damage from PTSD that are central to the development of and conceptualization of faith. So many times I have heard people say they have "lost their faith" or "lost the ability" to believe. The cognitive impairments and neurological damage caused by PTSD definitely affect this aspect of our lives.
Religion on the other hand is an institution, governed by a set statement of beliefs and/or doctrines, where like-minded believers can form a community of faith. But like any institution, it is made up of many individuals who will each have their own take on "faith"; and as with any other human community, you will find both the good and the bad.
It is perfectly normal for people to turn to their faith community in times of trouble, and when they feel they have been let down, judged, ostracized, etc., it can hurt twice as bad, as this is where we were taught to find refuge, understanding, love, etc. Not only does it cause a person to question religion, but it also hits at a deeper level causing an individual to question their faith.
For myself, I am working on my own faith and what it means to me. I really believe that once a person is strong in their own personal faith, the anxiety of religion can be resolved. When you know what you truly believe in; that becomes a part of "who" you are, and then regardless of what others say or do, they cannot touch that part of you.
It does not mean that I will attack, belittle or judge those who's faith is different than mine as that is not a part of my faith to do so. But ask me what and how I believe and I will share it with you. It is not my place to tell anyone what to believe in, but it is my place to live by the faith I chosen to believe in.
That is where I focus my own spiritual growth is being true to my God and myself in what I profess. I don't always do a great job as I am human, and that is where forgiveness comes into play. Forgiving oneself is also a huge part of healing from trauma and is much easier said than done. Much of our own anxiety comes from that inability to forgive and accept ourselves for who we are. Not what we think we should be or what others told us we should be.
So is it really religion that causes anxiety or our own personal concepts of religion? For me it is finding my faith and making it a part of who I am. Once I am strong in my faith, then I can practice religion with like-minded believers, and at that point the differences do not cause anxiety, as after all they are only human too and their faith is as personal to them as mine is to me.
Evil can be perpetuated in the name of anything. But along with evil exists the good and it is finding that good outside ourselves and making part of us that allows us to better withstand the evil. That is my own personal observation.