You exist in this earthly realm, in this body, at this time for a reason.  At the soul level you agreed to have this experience for your own growth—not as a human, but as a soul.  The human is the vehicle for the growth of the soul.  Why do you not hear from your loved ones who have passed every day or every time you ask?  Because this would impede your earthly lessons.  This would get in the way of your soul’s growth.  You must work at raising the quality of your consciousness for those moments of grace that result from a coherent state of consciousness when the veil seems to lift.  You must practice loving kindness here and now, not relying on it from above, and by doing so and having those momentary glimpses of heaven, you begin to get the bigger picture.  If all were revealed instantly and in an ongoing manner and you had constant access, where would be the growth?  This is a school of sorts, yes, at times the School of Hard Knocks.  Look around you.  There is much learning yet to be had.  The glimpses keep you moving toward the higher grades.