Death is not the ending of life, only of the fragment we call the self. Nor is death the opposite of life; it is part of life, as natural and essential as birth.
The self is grounded in the past. That is, the entity we call ‘me’ is made up of memories, knowledge, beliefs, ideas, which are based on past impressions, past experience. These give us a sense of continuity, but life is not continuous. Each moment of ‘now’ is entirely new: it has never been, nor will be again. We meet life with what we know, with the past, and so are rarely fully awake to the ‘now’.
Death is the ending of all we know, and many of us are afraid of it. We want the familiar to continue; we would like to enjoy another summer, to meet a loved-one one more time. But what we fear and desire are projections of our imagination, and hence are also based on the past. Not knowing death, what we truly fear is the idea of death. Each moment that we spend fearing or desiring what might be is a moment we are not fully awake to life.
To live fully in the present the self must end, which means ending all attachment to what has been. Then you are not separate from life, which has no beginning and no end.