Thank you for sharing your request and for your honesty about the pain and distress you are experiencing in your family. We hear how heavy the constant arguments have been for you, for your girlfriend, and for your mother, and we want to pray for you with care for your souls and for true peace in your home.
Scripture calls us to follow peace with all men and holiness, without which no one shall see the Lord. That reminds us that peace and holiness always go together. Peace is a great good, and those who make true peace are called sons of God, but not every kind of agreement is good in itself. Even those who do wrong can agree together, so concord is not good unless it is rooted in what is right before God. For that reason Christ said He came not to send mere peace on earth but a sword, because loyalty to Him must come before all else, and sometimes following Him brings division even in a household. At the same time He gives His own peace, which is different from a human peace that comes only from getting our own way.
The peace of God is steady and guards the heart. Human peace often comes from insisting on our will or from avenging ourselves, and it quickly falls apart. The peace of God rules in the heart when we yield our anger and our own plans to Him and ask Him to be the judge between competing desires. That peace surpasses understanding and keeps us in Christ Jesus.
In light of this we will not ask God to simply bless a dating relationship as it is, but we will pray for what is best for you according to His Word. We believe salvation is through Jesus Christ alone, and that marriage is a lifelong covenant of one man and one woman, with sexual intimacy and living together belonging only within that covenant. Whatever your future holds, God calls you now to purity, to holiness, and to honor for your parents.
We will pray that God will draw you, your girlfriend, and your mother closer to Himself, that each of you will know His forgiveness and grace through Christ, and that He will give you wisdom to discern His will. We will pray for healing from the emotional, mental and physical strain you described, for an end to harsh words and rudeness, and for grace to speak to one another with kindness and truth. We will pray that your mother will be given love and patience, and that you will be given humility and respect as you honor her, even as you seek wise and godly counsel about your future. We will pray that you and your girlfriend will commit yourselves to walk in holiness and self control, to seek the counsel of mature believers and pastors, and to not pursue togetherness at the cost of obedience to Christ. If marriage is the Lord's will for you in time, pray that you would pursue it in a way that is pure, patient, and pleasing to Him. If not, pray that He would give you clarity and strength to follow Him faithfully.
May the Lord grant you His peace, the peace that leads to love and holiness, and may He guard your hearts in Christ Jesus as you seek to please Him above all.