In his "Ascent of Mt. Camel", St. John says:
"I am appalled at what happens in these days-namely, when some soul with the very smallest experience of meditation, if it be conscious of certain locutions of this kind in some state of recollections, at once christens them all as coming from God, and assumes that this is the case, saying: 'God said to me . . . '; 'God answered me . . . ', whereas it is not so at all, but as we have said, it is for the most part they who are saying it to themselves."And in Book 2, Chapter 11 of the same work, he warns of diabolical illusion, especially when the soul is gullible and doesn't even consider the possibility of such illusion:
"There is always ground for fear that they proceed from the devil rather than from God; for the devil has more influence in that which is exterior and corporeal . . . As they are so palpable and so material they excite the senses greatly and the soul is led to consider them the more important, the more they are felt. It runs after them and abandons the secure guidance of faith, thinking that the light they give is a guide and means to that which it desires, union with God. Thus the soul, the more it makes of such things, the more it strays from the perfect way and means, i.e., the faith. Besides, when the soul perceives itself subject to these extraordinary visitations, self-esteem very frequently enters in, and it thinks itself to be something in the eyes of God, which is contrary to humility. The devil also knows too well how to insinuate into the soul a secret, and sometimes open, self-satisfaction. For this end he frequently presents to the eyes the forms of saints, and most beautiful limits; he causes voices well-dissembled to strike the ear, and delicious odours the smell; he produces sweetness in the mouth, and thrills of pleasure in the sense of touch; and all to make us long for such things that he may lead us astray into much evil. For this reason, then, we must always reject and disregard these representations and sensations."In Book 2, Chapter 16, he summarises his warnings; and it is interesting to note that the refusal to accept these apparitions is the proper attitude even in the case where they are truly from God, for as he explains, this is the way to test that they really are divine:
"I say, therefore, with respect to all these impressions and imaginary visions, and others of whatever kind they may be, which present themselves under forms or images, whether false as coming from the devil, or known to be true as coming from God, that the understanding is not to perplex itself about them, nor feed itself upon them; the soul must not willingly accept them, nor rest upon them, in order that it may be detached, naked, pure, and sincerely simple, which is the condition of the divine union."
Stop fixating on Fatima, Lourdes, Akita.
Start fixating on the Catechism, the writings of the saints and doctors of the Church.
Follow the advice of the doctors of the Church.
Learn doctrine, avoid apparitions, even those approved by the Church.