Your willingness to forgive, even while your heart still bears the wound of deep hurt, is heard before the Lord and before His people with much tenderness and prayer. To desire forgiveness and yet to feel unable to restore the same trust as before is not a contradiction of grace, but the honest cry of one who has been sorely wounded and who would obey Christ while also walking wisely.
The Scripture sets before us a divine forgiveness that is perfect and complete. "I, even I, am he that blotteth out thy transgressions," saith the Lord, and again, "There is forgiveness with Thee, that Thou mayest be feared." This forgiveness with God is without money and without price, without merit or preparation on our part, and it is given for Christ's sake. "God for Christ's sake hath forgiven you," and that forgiveness is eternal, without repentance. As you have read in these sermons, He has no buts in His forgiveness. We sometimes say, "I forgive him, but I will never trust him again." Not so the Lord, for He says, "I will not remember thy sins." He casts them behind His back and remembers them no more. If you tremble and with a penitent heart desire that forgiveness for your own sins, know that it is freely offered to you through the bleeding Saviour, through Gethsemane and Golgotha, and whosoever will put his trust in Christ shall find it, however great his sin has been.
We are then called to study that pattern and to copy it, "Even as Christ forgave you, so also do ye." This Christian forgiveness is a release of the debt before God, a refusing to hold the offense as a weapon of vengeance, a committing of justice and of the offender into the hands of Him who judges righteously. It is not a pretending that no hurt was done, nor a calling of evil good. It is a deed of the heart wrought by the Holy Spirit, by which we pray, as we have been forgiven, to forgive.
Yet forgiveness and reconciliation, though akin, are not the same. Forgiveness can be given in the heart before God in obedience to Christ, even when trust cannot be at once restored. Trust, as you have wisely discerned, is built upon truth and faithfulness over time, and where there has been repeated hurt, wisdom requires that trust be rebuilt slowly, and only as there is true repentance and fruit meet for repentance. The father in the parable did not entrust the prodigal with goods again before he had returned with a changed heart, and so in our earthly relations, to forgive the debt does not always mean to place again in the same position of vulnerability. To guard your heart, to set needful boundaries, and to seek safety is not unforgiveness.
Therefore let no one press you beyond what Scripture requires. The church is not to lay a burden upon a wounded conscience, but to come alongside with patience, to weep with those who weep, and to give you space to heal under the care of Christ. If counsel is offered, let it be for your protection and restoration, not for coercion. A faithful pastor or a wise and godly counselor may help you discern what wise boundaries look like in this season, and how to walk in both grace and truth with your mother.
You do well to bring all to Jesus and to trust Him where you cannot yet trust man. "Only trust Him, only trust Him," and you shall find Him able to keep that which you commit unto Him. He who has forgiven you without price will also be your strength to forgive, day by day, as He continues daily to forgive you. Bring your hurt, your memory, your fear of being wounded again, and lay it at His feet. Ask Him to make your forgiveness as sincere as His is complete, and to give you wisdom for every step of the path of obedience.
May the Lord, with whom there is forgiveness, grant you a clean breast by absolution as you make a clean breast in confession, and may He heal your heart so that whether reconciliation in its fullest sense becomes possible in time or not, you may live in the freedom of one who is forgiven and who, for Christ's sake, has forgiven, resting wholly upon the mercy of God in Christ Jesus.