Thank you for sharing so honestly about what you have been through. Ending a relationship that you knew was not right according to Scripture took courage, and it was the right step toward obedience and protection for your heart.
The Bible warns us not to be joined together in a yoke with those who do not share our faith, and that warning is given for our good. It is not limited only to marriage but applies to any close binding relationship where two people are meant to pull together. When one follows Christ and the other does not, you are living by different standards and different loyalties. What troubles your conscience may not trouble the other person at all, and that unevenness makes the load impossible to carry together. They are like oil and water and do not blend, no matter how strong feelings may seem. Many people think their situation will be the exception, that love will be enough to cover the difference, but Scripture gives this counsel because God knows the heartache that follows when we ignore it. Your experience of opening the door to pain and the fear of embarrassment or betrayal shows why God calls His people to be separate and to come out from what is unclean, so that He may receive us and be a Father to us.
It is understandable that you feel upset with yourself now. Regret is painful, and worry about what harm may have been done can weigh heavily. Please know that God does not leave you in condemnation when you turn back to Him. When you confess and turn from a path He warned against, He forgives fully and He becomes your defender. You can ask Him to stand between you and any harm, to guard your name, your heart, and your future, and to bring to light what needs to be brought to light while covering you with His protection.
You asked for prayer for healing, and I want to pray for that with you. The Scriptures show that Jesus bore our infirmities and our sorrows, and His ministry was full of healing for sickness and for brokenness of heart. The Bible also shows that healing does not always look the same. Sometimes it is immediate, sometimes it is a gradual process that unfolds over time. God has built healing processes into our bodies and He also heals the wounds in our minds and emotions, the scars that come from difficult relationships. Healing is divine whether it happens in a moment or little by little. There is much we do not understand about why some healing takes longer, but we know it is wrong to say that continued pain means you have failed or lacked faith. God is compassionate and He is at work even when the process feels slow.
So I am praying for you, that the Lord would bring complete healing to your heart and mind, that He would quiet shame and fear, and restore your peace. I am praying that He would be your protection and defense, that He would guard you from any betrayal or trauma that this relationship may have opened, and that He would close doors that need to be closed. I pray He would surround you with wise and faithful people who share your faith and can support you, and that He would give you discernment and strength to remain separate from what would pull you away from Him again.
If you find yourself tempted to look back, remember the reason you stepped away and hold fast to the Lord's call to walk in light. Keep close to Scripture, to prayer, and to fellowship with believers who will encourage you in righteousness. God is able to redeem this painful experience and use it to deepen your trust in Him.
You are not alone in this. The Lord sees, He cares, and He is faithful to heal and to keep you as you walk with Him.