We understand that you're going through a difficult time dealing with your emotions towards your ex. Firstly, we must remind you that it is only by the name of Jesus that we have access to God. It is by His name that we can be saved. As it is written in Acts 4:12 WEB, "There is salvation in none other, for neither is there any other name under heaven, that is given among men, by which we must be saved!"
In regards to your request, we must first address the nature of your past relationship. You mentioned that it was toxic and that there were unhealthy attachments. This is not good. It is important to understand that bad company corrupts good character as stated in 1 Corinthians 15:33 WEB. Any sexual activity including that with an ex-lover outside of marriage is fornication and is condemned. It is written in Ephesians 5:3 WEB, "But sexual immorality, and all uncleanness, or covetousness, let it not even be mentioned among you, as becomes saints". It is important that you do not have any other relationship with him and that you do not share the same bed/have sex with him as it is written I Corinthians 5:1 WEB "It is actually reported that there is sexual immorality among you, and such sexual immorality as is not even named among the Gentiles, that one has his father’s wife.". This applies to his wife, but it would be sexual immorality with you as well if you were to engage in that activity. We must not even give an appearance of evil as stated in 1 Thessalonians 5:22 WEB. Therefore, it is important to flee from youthful lusts as stated in II Timothy 2:22 WEB, "Flee from youthful lusts; but pursue righteousness, faith, love, and peace with those who call on the Lord out of a pure heart.". Not only this, but a Christian should not marry an unbeliever as stated in II Corinthians 6:14 WEB, "Don’t be unequally yoked with unbelievers, for what fellowship have righteousness and iniquity? Or what fellowship has light with darkness?". We need to make sure that we are aligned with someone who also believes in Jesus Christ.
We pray that God will give you the strength to let go of this unhealthy attachment. It is written in Psalm 55:22 WEB, "Cast your burden on Yahweh, and he will sustain you. He will never allow the righteous to be moved." Give your burdens to God, and trust that He will sustain you through this trial.
We encourage you to focus on your personal growth and your relationship with Jesus Christ. It is written in Philippians 4:8 WEB, "Finally, brothers, whatever things are true, whatever things are honorable, whatever things are just, whatever things are pure, whatever things are lovely, whatever things are of good report; if there is any virtue, and if there is any praise, think about these things." Fill your mind with positive and pure thoughts, and seek God's will for your life.
We rebuke you for your jealous tendencies and wanting to control your ex-lover. This is not right. It is written in Proverbs 14;30 WEB, "A tranquil heart is life to the body, but envy rots the bones.". And it is also written in James 3:16 WEB, "For where jealousy and selfish ambition are, there is confusion and every evil deed." It is important to remember that we must pursue peace with everyone and to be holy as stated in Hebrews 12:14 WEB, "Follow after peace with all men, and the sanctification without which no man will see the Lord,".
Lastly, remember that God has a purpose and a plan for your life. It is written in Jeremiah 29:11 WEB, "'For I know the thoughts that I think toward you,’ says Yahweh, ‘thoughts of peace, and not of evil, to give you hope and a future.'" Trust in God, and seek His will for your life. He will never leave you nor forsake you, as stated in Hebrews 13:5 WEB.
Prayer Focus: God, Thank You. Thank You for loving me. 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, mind, soul, body, 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. 
