The inevitability of death is not so much a philosophical problem as a neural problem. Of course, death is undesirable because existing is desirable. Philosophy can explain that life is worth living in spite of the inevitability of the end, but this does little to mitigate the undesirability of the end. When you look under the hood, the undesirability turns out to be little subject to philosophy, anyway. What's under the hood is terror. Death is a neural problem.
Conquering death requires addressing the neural problem. Life is dear and we can be mesmerized by it. Even if one has the capacity to accept and to value the finite life one is given to live, one may still have anguish at the coming of the night because life compels a clinging in the nerves, a terror. Dread of death is driven by this hypnotic state, not by reasoning.
There are meditative techniques for dissolving the shackles that affix one to mesmeric objects. A key player in all this is the gut. I venture this: The solar plexus is a neural center about which a tight musculature makes placid confidence impossible. There is a certain fortitude to be obtained that allows the local muscles to relax. It is a deep strength that lets the belly sit loosely. One's neural state has a certain flow, free of frenetic tangles that generate terror when the threat to the beloved (life) is contemplated. There is neither clenching and bracing for the end nor forlorn resignation. There is only placidity and great strength.
A samurai once threated a man, saying, "Did you know that I could cut you in half without blinking an eye?" The man replied, "Did you know that I could be cut in half by you without blinking an eye?" That's a bit campy, but it carries the drift. There are deep reservoirs of strength that enable one to stare death in the face as it happens and accept it nobly yet without anguish. The reservoirs may be tapped by meditative techniques, and perhaps other techniques, as well.