We have already shown the difference between simple feelings of ups and downs possibly caused by a million things, and the essential next step, that is, the spiritual nature of consolation and desolation. I don't think we can repeat that enough. Without the ability to make that distinction, you won't be able to get much further. (That's like knowing the difference between muscle aches caused by your jog last night, and a muscle illness which needs to be cured.)
Most failures to discern God's voice properly are failures to distinguish between spiritual and non-spiritual movements of the human soul.
Spiritual consolation or desolation cannot be created or caused by you - they essentially come from above or below.
As well, we underlined the differences of souls, and showed that God and the Devil speak in different ways based on the level of spiritual growth that a given soul has attained to, thus the necessity of self-knowledge for proper spiritual discernment. (Like knowing your own weight, height, and bench-press limit.)
We already saw what you should not do. When you are under fire from desolation, spiritual changes are always bad. (Duck or Rabbit?) Here, on the other hand, is what St. Ignatius suggests that you should do.
4 Secrets for when you are Under Fire:
1. Pray! ASK God for help. When the going gets rough, in whatever manner you get hit by difficulties, your first refuge should be God himself. His grace and his power are infinite. The concrete desolation you often feel is exactly the opposite, you feel prayer is useless. All the more reason to raise a sincere prayer of petition to the one you know can help.
2. Meditate! This may include calling to mind all the moments God has helped you in the past: when he answered your prayers, when he gave you great consolation. As well, this could include meditation on the word of God. Gospel truths are often the exact texts which will dispel the untruthful thoughts spinning around in your head following the attacks of desolation.
3. Reflect! Put things into proper perspective. See your feelings and thoughts as GOD sees them. Take a step away from yourself and see what is actually going on. Once you realize that you are truly being attacked by desolation - that you have not chosen to feel the way you do and to think the thoughts that result from those feelings - then you will be much better prepared to battle against them.
4. Sacrifice! Lastly, conquer the devil. If every time he tempts you with desolation, you respond by increasing your sacrifice just a bit, then he will soon realize that attacking you is pointless. For example if you normally pray 30 minutes every evening, and are attacked with the lie that "prayer tonight is useless, since I feel so empty." Then the best response is to pray 35!! minutes.
Spiritual desolation might be a common attack of the Devil for those who are striving to purify their sins and grow closer to God, but the remedies are also just as common as water, clean air, rest and exercise for those striving to remain healthy.
And at the end of the day, what matters more? Your spiritual or physical health?