God is Love. But unconditional love implies giving freedom to the object of love. And we are free, loving particles of God. Any action, thought or word we take, if it is not based on unconditional love, falls under the law of karma and produces either favorable or unfavorable consequences. And every event we experience has a cause, nothing is accidental. Thus, if someone curses us or puts an evil eye on us, it means that we deserve it.
It is impossible to curse a saint! Even the very thought of it can bring many misfortunes. The best protection is purity of thoughts, which gives a strong biofield and a bright aura, and then all the bad energies that are sent to us will return.
But unfortunately, many people find it easier to pay a lot of money for the process of removing spoilage than to forgive their neighbor.
In India, such treatment is compared to bathing an elephant. The elephant goes into the water, gets thoroughly washed, but when he comes out, the first thing he does is to start rolling in the dust... So in this question, too, everything depends on the outlook, character and purity of consciousness.
If you are strongly afraid of something, envious of someone, offended (even if you were offended not "deservedly"), condemning someone, you are flattening yourself and your loved ones, especially children, yourself. If you do something bad to someone, do not help a loved one in trouble, betray someone, spread gossip, slander on a lofty person, it is already a curse on yourself and, often, your own kind. If you are disrespectful to your parents, do not take care of them, that is also a kind of curse of yourself.
Spoiling is when you spoil your energy field, physical body and destiny with selfishness, greed, dejection, anger, etc.
The more jealous a person is, the easier it is to "pierce" him. Even if someone looks at his new thing with a little envy, that thing is either lost or broken. But, with that in mind, one should in any case boast less, stay away from selfish, envious creatures of God. If they have strong energies, they can penetrate anyone for a while.