How does "soul exchange" work?

I find this topic fascinating and I'm not sure what to make of it. To make a long, boring story very short, about 10 years ago I was a very different person. I was an extremely devout, very judgmental fundamentalist Christian and had been one for years. I had become a bit disillusioned with the church over some things that happened, but then I ended up having some major medical problems that required surgery. I was told I may not live more than a few months.

Most people probably would have clung even tighter to their faith with that news, but instead, after I came home from surgery I completely broke away from my former faith. I stopped being interested in many things that I was before and I developed a new interest in things I had no interest in at all. I won't take the time to explain what those things are unless someone really wants to know, but today I am a very, very different person and the turning point was my illness and surgery. I studied many different faiths and almost turned to atheism at one point, but today I am something that I never would have dreamed of becoming back then: a neo-pagan spiritualist.

I had always had experiences with what many would call ghosts and spirit guides, since I was a child, but all my adult life I had attributed them to demons. Never in my wildest dreams did I ever think I would turn my back on my former faith and become pagan anything. The fear of hell alone was quite crippling to me and all that changed with the illness and surgery.

I have no idea if this is related to the topic of this thread or if it's other factors or just coincidence, but it intrigues me. I have retained very little knowledge of my former faith, especially when you consider how much scripture I had memorized at one time, for one thing. It's all kind of weird, really.