Personally, I would drop the whole "she is not seeing the TRUTH, I need to convert her!" mentality and sense of superiority.

You think psychedelics are a door to the spirit realm, but it's perfectly possible that they are not. An important aspect about psychedelics is that they are supposed to let you keep an open mind on these matters and avoid dogmatisms (one way or the other), especially when trying to get others to conform to your views.

YOU value psychedelics as a "spiritual path" and that is what seems to work for you, but the psychedelic experience is not for everyone, not all people have the same neurochemistry and many of them will not get real benefits out of it or interpret it in the same way, and that's ok.

If the problem is about your significant other not sharing a big aspect of your life with you that you feel is simply too important, I can see you trying to get her to enjoy a low dose of other psychedelics (like lsd or mushrooms) and slowly start to build a "common ground".