I would approach this with both Catholic faith and sober prudence.
The first thing I would say is this:
Do not give a curse more power in your mind than the Catholic faith gives it in reality.
The Church certainly takes the reality of Satan and demonic activity seriously. But Catholic theology does not teach that another person’s curse has some automatic, magical power over a baptized Christian. The Catechism specifically warns against magical thinking and tells Christians to place themselves confidently in God’s providence. (Vatican)
1. Don’t try to fight a curse with another form of magic
This is extremely important.
Don’t consult mediums, psychics, tarot readers, occult practitioners, “curse breakers,” or people who claim special supernatural knowledge about who is attacking you.
The Catechism rejects divination and occult practices, including attempts to manipulate hidden spiritual powers. (Vatican)
In other words:
Don’t fight darkness by borrowing its vocabulary.
Stay entirely within Christ and His Church.
The Forgotten Way by Matthew Kelly would be extremely helpful.
The wording of your letter is a sure sign That you are using Words incorrectly.
2. Return to the ordinary weapons of Catholic Christianity
If you believe you are experiencing something spiritually disturbing, I would make your life boringly Catholic for a while.
That is actually quite powerful.
- Go to Mass regularly.
- Receive the Eucharist worthily.
- Make a good confession.
- Pray the Our Father slowly.
- Pray Psalm 23, Psalm 27, Psalm 91, and Psalm 121.
- Pray the Rosary.
- Make the Sign of the Cross deliberately.
- Keep a crucifix in your home.
- Ask your priest to bless your home.
- Ask for a priestly blessing for yourself.
- Continue ordinary responsibilities rather than organizing your entire life around the supposed attack.
The goal is not to become preoccupied with demons.
The goal is to become preoccupied with Christ.
3. Don’t try to identify the people supposedly doing this
This is another important safeguard.
You said you believe it may be “one or more people casting a curse continuously.”
I would not try to determine who they are unless you have ordinary, concrete evidence of actual harassment or wrongdoing.
There is a huge difference between:
“Someone is threatening me and I have evidence.”
and
“Something frightening is happening, therefore someone must be spiritually attacking me.”
The first can require practical action. The second can become a frightening loop that feeds upon itself.
And even if someone really is wishing you evil, their hatred does not become your spiritual destiny.
4. Remember who has the greater authority
This is perhaps the heart of the matter.
The Christian doesn’t say:
“I hope the curse isn’t stronger than my faith.”
The Christian says:
“Jesus Christ is Lord.”
The power of Christianity does not depend upon your ability to out-pray somebody else’s curse.
It rests upon Christ.
St. Paul gives us the great framework in Ephesians 6:10-18: put on the armor of God. Notice something fascinating about that passage. Paul doesn’t tell Christians to become experts in demonic activity.
He tells them to put on:
truth, righteousness, faith, salvation, the Word of God, prayer and perseverance.
That’s a very different orientation.
5. Don’t turn sacramentals into magical shields
Holy water, blessed medals, the Rosary, crucifixes, scapulars and other sacramentals can be beautiful aids to Christian faith.
But they aren’t magical objects.
The Catechism specifically warns against treating religious practices as if their external performance possesses magical power. (Vatican)
So rather than:
“I need this object because otherwise the demon can get me,”
think:
“This reminds me that I belong to Christ.”
That distinction is enormous.
6. Talk to a good Catholic priest
I would particularly recommend speaking privately with your pastor or another experienced, balanced Catholic priest.
Tell him exactly what you’ve told me.
You don’t need to convince him that a demonic attack is occurring. Simply explain what you’re experiencing and ask him to help you discern it.
The Church does have a formal ministry of exorcism, but that is very different from an individual deciding that he or she needs an exorcism. The Church exercises considerable discernment regarding such situations. The USCCB describes exorcism as a prayer of the Church for protection or liberation from demonic influence, exercised through ecclesial authority. (USCCB)
A priest can therefore help you distinguish among spiritual temptation, psychological distress, ordinary human conflict, and genuinely unusual spiritual phenomena without jumping to conclusions.
7. One prayer I particularly recommend
You don’t need elaborate words.
When you feel frightened, simply say:
“Jesus Christ, Son of the living God, have mercy on me. I belong to You. I place myself, my mind, my body, my home, and my future into Your hands. I reject every evil and place my trust entirely in You. Mary, Mother of God, pray for me. Saint Michael the Archangel, pray for me. Amen.”
Then stop.
You have prayed.
Leave the matter with God.
That last part may actually be the hardest part.
8. And here’s a particularly important Catholic principle
The Catechism says that the Christian attitude toward the future is to place oneself confidently in God’s providence. (Vatican)
That gives us a remarkable spiritual strategy:
Don’t investigate the darkness endlessly.
Turn toward the Light.
If something genuinely supernatural is occurring, Christ is not helpless.
If something psychological or physical is contributing to what you’re experiencing, Christ is not threatened by that either.
If another human being is actually harassing you, Christ does not require you to tolerate it. You can take appropriate practical and legal steps.
And if fear itself is beginning to take over your thinking, seeking help from a physician or mental-health professional is not a failure of faith. God’s providence can work through medicine and human wisdom too.
One final thought,
You don’t have to become a spiritual detective.
You are a Christian.
Your assignment is considerably simpler:
Stay close to Christ. Stay close to His Church. Receive the sacraments. Reject occult practices. Don’t accuse people without evidence. Use ordinary prudence. And refuse to let fear become the center of your spiritual life.
Renew your baptismal promises each time you bless yourself when entering church.
You will emerge from this a stronger Catholic And have stronger faith. Do not fear!
The devil, real or imagined in a particular situation, does not get to become the main
character in your relationship with God.
Christ does. 
Catechism of the Catholic Church, First Commandment