If the person who committed suicide at some time accepted Jesus' death on the cross as payment for his sin debt and asked Him into his life, he is forgiven. If a person has ever taken that step and received Christ as Savior, nothing can alter the truth that, as children of God, we are forgiven. Even when we rebel against God, He is faithful to keep His Word. On the other hand, there is no such assurance for the one who commits suicide and has never taken that step of faith in Christ, except the assurance of eternal separation from God. The fact that God's grace is sufficient and that forgiveness is available even in the case of suicide should never be taken as permission to follow through with the temptation to commit suicide.
Suicide is never the right decision.
No one enjoys suffering. All of us sympathize with those who hurt, both physically and emotionally. When nothing we try works, God has promised that He is able to sustain us. Cry out to God. The LORD is near to those who have a broken heart, and saves such as have a contrite spirit.