I think you can basically look at it like this:

The mind can only understand the events that surround it by stringing those events into narratives that make logical sense. In other words, we tell ourselves stories about things that are happening in our lives to be able to better comprehend those things. The stories themselves may or may not be true.

When it comes to religious thought, that type of thinking has been the most profound line of thought in human history. Of all species in the world, man is the only one that can look at him or her-self and ask 'why', and because of this unique trait, people's question of why has so far predominantly led to the answer of: "because God".

So it's no surprise that when people's minds become more active and lead toward psychosis, that the ultimate answer the narrative leads to is 'because God'. But if you can imagine a world where the 'concept' of God just didn't exist, then the delusions we had about God would not be possible. We would still become delusional yes, but our mind wouldn't be able to comprehend a dream-like state that included God. So that fact alone falsifies that psychosis has anything to do with God.

For what it's worth, my first bout of psychosis also had religious elements, but once I came out of that psychosis I realized that those religious elements were illusion, because I understood that the way I was seeing things while psychotic were just my way of perceiving the world at the time, and not how the world actually was.

So all that said, it's not so much that accepting that your visions were illusion falsifies Christianity or anything, it's that you were in something of a waking dream, and your Christian faith is a completely separate thing from whatever that experience was.

My suggestion for you is to completely write off any of your psychotic experiences, and do your best to tirelessly search out what the truth of any situation is at any time. Because the truth is what's real, and when you know what's actually happening, you're more able to deal with your life.