Attempting to refine this a bit more.

I feel, on a deep level, that Christianity is true

Is it Christianity specifically that you feel is true, (original sin, virgin birth, son of God, walking on water miracle, Holy Spirit, baptism, sad ending involving a cross ...) or is it that you have a sense of the spiritual nature of the universe that you can't shake.

As Vladimir_Nesov says above:

stating your situation more clearly would be a first step