We are truly saddened to hear about your friend's struggles, but we are thankful that you have reached out for prayer and support. Spiritual warfare is very real, and it is clear that your friend is in the midst of an intense battle. The Bible tells us that our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms Eph 6:12 WEB.
Firstly, we need to understand that the enemy is attacking your friend because he wants to destroy him. The enemy comes to steal, kill, and destroy, but Jesus has come so that we may have life, and have it to the full John 10:10 WEB.
Your friend's struggles with suicide and loneliness are serious, and we must pray fervently for God's intervention. We know that God is close to the brokenhearted and saves those who are crushed in spirit Psalm 34:18 WEB. We also know that God has not given us a spirit of fear, but of power, love, and self-control 2 Tim 1:7 WEB.
Regarding his struggle to submit fully to God, we must remember that submission is a choice that each person must make. God will not force himself on anyone. We must choose to follow him and obey his commands. Jesus said, If anyone desires to come after me, let him deny himself, and take up his cross, and follow me Mat 16:24 WEB. This is a call to die to ourselves and live for Christ.
Let us pray together for your friend:
Heavenly Father, we come before you in the name of Jesus Christ, lifting up our friend who is going through intense spiritual warfare. We pray that you would strengthen him in his faith and give him the power to overcome the enemy's attacks. We rebuke the spirits of suicide and loneliness that are tormenting him, and we command them to leave in the name of Jesus. Lord, we ask that you would surround him with your love and peace, and that you would give him the courage to submit fully to you. Help him to know that you are always with him, and that you will never leave him nor forsake him. We pray that he would come to know the saving of Jesus Christ if he has not already. In Jesus' name, we pray. Amen.
We encourage you to continue to stand in the gap for your friend and to support him in any way you can. Remind him of God's promises and encourage him to seek God's face in this time of need and adversity. Also, we would like to encourage your friend to reach out to local church and set up an appointment with a Pastor or Elder. We are called to live in community with other believers, and it is important that he has the support of the body of Christ during this time.