The first presupposition behind this painting is that Man is fallen. That means we have a predisposition to sin, that is to say, to voluntarily choose to do what we should not - in short, sin is an abuse of free will, which can only be licitly used to choose the good. A person might feel the temptation to do something he should not. We are enticed. It seems to promise happiness. "I could have X, if I only did this evil thing Y." Do we give in? Do we indulge? When we do, we have sinned. We have lost the spiritual battle. Ultimately, the smoke evaporates, the mirrors crumble, and we are left with empty hands and the damage done, above all to ourselves.

Then, there is the fallenness of some angels, the demons, immaterial beings of various species of superior intellect and power who - while on a short leash - are still able to act on fallen men in malicious ways to lead them toward self-destruction. This "short leash" should be expanded. If God did not constrain the power of the demons, it is anyone's guess the devastation of the universe they could wreak. But since God is master of all creation, even the demons are pressed into the service of the good, but instrumentally. Even evil is made to further the divine plan. Thus, God permits the demonic assaults on St. Anthony as a kind of spiritual training for him, part of which involves developing a greater surrender of self to God.

Now, someone who doesn't believe in demons won't find demonic activity and role in human sin compelling. I suspect that is the motivation behind your question. Someone who doesn't can at least recognize the struggle with various temptations and the struggle of the moral life. In that sense, if these are the sorts of things you struggle with, then you may find the image you have in mind helpful. But, of course, to know how one should act and choose, one should also know where one is going. St. Anthony knew his destination, and this destination is not arbitrary. That's what he suffered for and a large part of the reason how he came to know how to move in that direction and why he was able to bear it all.