One way to come to terms with death is to understand it philosophically.
The one inevitable fact in our lives is that we will all die- or, "pass over" from the physical to the spiritual world. The transition from the physical realm to the spirit is not an ending, it is a transformation - to another state of consciousness.
Physical life can best be described by the Sanskrit word "maya". An illusion. According to Hindu philosophy, everything that is changeable and subject to decay and has a beginning and an end is 'maya' Everything that is indestructable and eternal is reality. Since our life on Earth is temporary, it is 'maya'. Mistaking the facade for reality, we are in a state of 'maya'
Believing that physical life is the only form of existance is an illusion. And thinking we are dead once physical life ends, is the biggest illusion.
So, the person is not dead - he or she has passed over from physical to the spiritual life.
The other way to come to terms with the death of a near and dear one, is to focus on all the goodness he or she left behind. The person's thoughts, deeds, teachings, contributions towards shaping the family, the children. Principles and values. In short his or her character, and what learnings could be derived from it.
To continue to follow those guiding principles, practise those values and learn from the actions that the departed one was known for.
Grieving is natural. But to also cherish memories. And to also thank God for having ended his or her suffering.
And paying the ultimate tribute to the departed soul - celebrating life by living it the way he or she loved to.