We understand your struggle with a guilty conscience and the complexities that come with it. You're right, the law of the Lord is perfect, reviving the soul, and His testimony is sure, making wise the simple. We must remember Psalm 19:7-8, "The law of the Lord is perfect, reviving the soul. The testimony of the Lord is sure, making wise the simple. It is also a school master leading us unto Christ."
Firstly, it's crucial to understand that guilt is often a result of our own failures or sins, but it can also be a burden we carry due to the expectations of others or our own perceived shortcomings. As believers, Christ offers us a guiltless state if we repent. Romans 8:1-2, "There is therefore now no condemnation to those who are in Christ Jesus, who don’t walk according to the flesh, but according to the Spirit. For the law of the Spirit of life in Christ Jesus made me free from the law of sin and of death."
As you correctly mentioned, whatever is not of faith is sin. Romans 14:23, "Whatever is not of faith is sin.". It's important to act in faith and live by it, abiding in Christ. False guilt, often a result of people-pleasing, can be overcome by establishing healthy boundaries and understanding our identity in Christ and His expectations of us rather than the world's.
Let's pray together
Dear Heavenly Father, we come before you in Jesus' name, lifting up our brother/sister who is burdened by guilt. We ask that you grant them the gift of faith, hope, and love. Help them to discern between true and false guilt, and to live a life that is pleasing to you, not the world. We also ask that you guide them in establishing healthy boundaries and abiding in Christ. We know that whatever is not of faith is sin. Please help them act in faith and live by it. And above all, help them realize they are justified through faith in Jesus and not condemned. We pray for peace and joy to be restored in their heart and mind. We ask this all in Jesus' name. Amen.
We encourage you to continue meditating on God's word. Be reminded of Colossians 2:13-14, "You were dead through your trespasses and the uncircumcision of your flesh. He made you alive together with him, having forgiven us all our trespasses, wiping out the handwriting in ordinances which was against us; and he has taken it out of the way, nailing it to the cross.". Stay strong in your faith and do not be troubled by guilt.
Also, while you discussed faith, hope, and love you did not mention Jesus Christ, Jesus, or Christ or an abbreviation such as IJN (In Jesus Name), then make sure to discuss this issue. It is only by the name of Jesus that we have access to God. Also, there is no other name by which we can be saved. "So then they that are of faith, are blessed with the faithful Abraham. Now to Abraham were the promises spoken, and to his seed. He doesn't say, "To seeds," as of many, but as of one, "To your seed," which is Christ. Now I say this: A covenant confirmed beforehand by God in Christ, the law, which came four hundred thirty years after, does not annul, so as to make the promise of no effect. For if the inheritance is of the law, it is no more of promise; but God has granted it to Abraham by promise. What then is the law? It was added because of transgressions, until the seed should come to whom the promise has been made. It was ordained through angels by the hand of a mediator. Now a mediator is not a mediator of one, but God is one. Is the law then against the promises of God? Certainly not! For if there had been a law given which could make alive, most certainly righteousness would have been of the law. But the Scriptures imprisoned all things under sin, that the promise by faith in Jesus Christ might be given to those who believe." Galatians 3:9-22.
In the future, do not forget to mention Jesus Christ while discussing faith, hope, and love.
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. 
