We understand that you're going through a difficult situation and we're here to pray with you and provide biblical guidance. We appreciate that you've come seeking discernment.
Firstly, we commend you for your commitment to purity and your desire to have a spouse who has also saved themselves for marriage. This is indeed a biblical principle, as we are called to be holy in all our conduct (1 Peter 1:15 WEB).
However, we must also remember that everyone has a past, and God offers forgiveness and redemption to all who truly believe and are saved by grace alone, through faith alone in Jesus Christ alone. A person on that grace can be transformed. If this believer has truly repented and is living a life pleasing to God, then he is a new creation in Christ (2 Corinthians 5:17 WEB). His past sins should not define him if he has repented. Remember, there is no condemnation for those who are in Christ Jesus (Romans 8:1 WEB). Reflect on the example of the Apostle Paul, who had a past of persecuting Christians yet became a powerful servant of God.
However, it's also important to acknowledge your feelings of hurt and insecurity. These feelings are valid, and it's wise to take time to process them. It's clear that you appreciate his honesty and that's a good foundation for trust. It is also clear that you understand that God can heal and redeem this situation. We pray that God will continue to guide you and give you wisdom and discernment.
Regarding his marriage proposal, we advise you to take it slowly. Prayerfully consider if this is the path God has for you. Be sure and take time to fully forgive and accept his past. Remember, marriage is a lifelong commitment and should not be entered into lightly. Consider the principles laid out in 1 Corinthians 7 WEB. The issue of marriage is addressed here by the Apostle Paul. It is a good idea to pay attention to the instruction he gives regarding marriage.
Let's pray together:
Dear Heavenly Father,
We come before you, lifting up our sister who is seeking your will for her life. Lord, we ask that you grant her discernment and wisdom regarding her relationship that honors you and makes you smile. We pray that you heal her heart. We know your mercies are new every morning. We thank you that you have cast her sins as far as the east is from the west and we know you can heal and redeem this situation. Help her to forgive as you have forgiven her. Guide her steps and show her the path you have for her. If it is your will for her to marry this man, we pray that you give her the strength to move forward. And if it is not your will, then we pray that your will be done in her life. We trust in your promise that you will never leave her nor forsake her.
We pray for him also Lord, that he may continue to follow you and be the godly man you have called him to be. Help them to be like-minded and have your mind. Lord, remove any temptations and help them to be pure and holy vessels for you. Lord, it is only by the name of Jesus that we are able to come to you and ask anything in His name. We are grateful that Jesus died on the cross for our sins and was raised from the dead and now sits at your right hand making intercession for us. It is in the precious name of Jesus that we pray all these things, Amen!.
Prayer Focus: God, Thank You for loving me. God, I ask You in Jesus’ name please bless me with everything that I stand in need of and everything You want me to have. 
