Holly Im sorry for your loss. I look at my dad's picture everyday and cant believe that he died. Death is not natural so your mind is trying to understand something that is not natural.
One thing that has helped me tremendously is the Bible. Jesus said: “I am the resurrection and the life. He that exercises faith in me, even though he dies, will come to life.” according to John 11:25. The Bible teaches that the dead will live again. While Jesus was on earth, he showed that he is able to resurrect the dead. On one occasion, he resurrected a 12-year-old girl. How do you think her parents react? They “were beside themselves with great ecstasy” according to Mark 5:42. Under the rule of his Kingdom, the heavenly King Jesus Christ will resurrect untold numbers of people to life here on earth—but under peaceful and righteous conditions. (Acts 24:15; 2 Peter 3:13) Imagine the great ecstasy when the dead come back to life and are reunited with their loved ones!
I hope these scriptures bring you some hope and comfort in your time of loss.