Do not be grieved for the joy of the Lord is your strength (Nehemiah 8:10 NASB)
Death of a loved one is difficult to bear. You feel like you have lost a part of yourself. When a husband or wife passes, you are losing a part of yourself because you become one flesh and in Christ, you are one.
Loss is hard in any case whether spouse, child, or friend, but God has showed us that we have strength and joy in Him. When we look to Him for comfort, He is there to give us peace and our joy becomes full.
Grief may last for a night, but joy comes in the morning. Each day that you look to Christ for comfort during your grief, peace will come. At times, you may feel like you cannot go on, but be encouraged. If you have a bible, pick it up and read through the Psalms. You will find comfort and in time, joy.