We understand that you are feeling physically ill and experiencing profound distress, even disgust, towards someone who is causing you great turmoil. This person is invading your thoughts and causing you to feel threatened. First, we want to assure you that God is a refuge and strength, a very present help in trouble (Psalm 46:1 WEB).
First we need to correct an issue with your request. You began addressing your prayer with 'Dear god'. We need to make sure that we are praying to the God of the Bible. The Bible tells us 'For there is one God, and one mediator between God and men, the man Christ Jesus,' (1 Timothy 2:5 WEB). In prayer we are to go through Jesus. This is why we pray in Jesus' name. Jesus said "Most certainly, I tell you, whatever you may ask the Father in my name, he will give it to you. (John 16:23 WEB) and Most certainly I tell you, whatever you may ask in my name, I will do it. '(John 14:13 WEB) and 'If you will ask anything in my name, I will do it. (John 14:14). Notice that we are asking in Jesus' name and not praying to Jesus.
We need to pray to God through Jesus Christ and in his name. Not just to God only. There is no other name under heaven whereby we can be saved but through Jesus' name (Acts 4:12 WEB). This is important because the Bible tells us 'For "Whoever will call on the name of the Lord will be saved." How then will they call on him in whom they have not believed? How will they believe in him whom they have not heard? How will they hear without a preacher?' (Romans 10:13-14 WEB). This is really a matter of being saved or not saved. You must be a believer in Jesus Christ.
If they hear and believe in Jesus Christ, they can call on the name of Jesus and be saved. We ask do you believe in Jesus Christ as your Savior? This is very important to the issue. If you do not believe in Jesus as your savior we can introduce you to him for repentance and salvation from sins.
As you call on Jesus for the issues you are having with the person doing things to you, let us pray:
Let us pray.
Almighty God, we come before You in the name of Jesus Christ, lifting up this person who is feeling physically ill and deeply disturbed by the actions of another. Lord, You are our strong tower and our shield (Proverbs 18:10, Psalm 3:3 WEB). We ask Jesus to protect their mind, body, and spirit from this invading person's malicious intentions. There is power in the name of Jesus. 'and through him to reconcile all things to himself, by him, whether things on the earth, or things in the heavens, having made peace through the blood of his cross.' (Colossians 1:20 WEB).
We also know that the source of these kinds of things is spiritual. In those cases we can use the armor of God in (Ephesians 6:10-17). Also the weapons of our warfare are mighty before God to the casting down of strongholds. (2 Corinthians 10:4). The biggest weapon we have is the name of Jesus. The Bible says 'Therefore God also highly exalted him, and gave to him the name which is above every name; that at the name of Jesus every knee should bow, of those in heaven, those on earth, and those under the earth,' (Philippians 2:9-10 WEB). So the name of Jesus is not just about salvation but also the power that we have over all things. We need to walk in this power.
We pray that You, Lord, will rebuke this person and remove them from their life. We ask that You will heal any physical illness and grant them peace and soundness of mind. Lord Jesus, please reveal Yourself to him/her. We pray for both their physical safety and mental comfort and strength.
We also offer this advice: Seek support from fellow believers and professional help if needed. You do not have to face this alone. The Bible tells us 'Is any sick among you? Let him call for the elders of the assembly, and let them pray over him, anointing him with oil in the name of the Lord, and the prayer of faith will heal him who is sick, and the Lord will raise him up. If he has committed sins, he will be forgiven. Confess your offenses to one another, and pray for one another, that you may be healed. The insistent prayer of a righteous person is powerfully effective.' James 5:13-16 WEB). The key is getting the elders which are believers to pray for you with your in the name of Jesus and having faith. The results are healing and even forgiveness of sin.
Remember that God has not given us a spirit of fear, but of power, love, and self-control (2 Timothy 1:7 WEB). Trust in Him, and He will deliver you from this distress. In every situation, know that God is with you and will never forsake you (Deuteronomy 31:6, Hebrews 13:5 WEB). 'Be anxious for nothing, but in everything by prayer and petition with thanksgiving, let your requests be made known to God.' (Philippians 4:6). God loves you cares for you (1 Peter 5:7 WEB).
We further encourage as we rebuke the acts of the person causing distress, that our battle is really not against flesh and blood. We have boldness in the day of judgment because as he (Jesus) is, even so are we in this world (1 John 4:17).
We are glad that you turned to God in prayer to seek help in your difficulty. We hope and pray that you will continue to seek Jesus Christ in everything that you do.
Prayer Focus: God, Thank You for loving me. Thank You for loving me, Jesus. God, I ask You in Jesus’ name bless me with everything that I stand in need of and everything You want me to have. Bless me to know You in truth, fall in love with You with all my heart, soul, mind, and strength and never fall out of love with You. Bless me to have an ever growing closer stronger, more intimate relationship with You. Bless me with the love, desire, strength, and the spirit of obedience to always delight myself in You, seek first Your kingdom, and Your righteousness. Help and strengthen me God to always respect and obey You. Bless me to trust You with all my heart, acknowledge You in all my ways, and lean not to my own understanding. 
