How well do you know the Bible? The New Testament tells us that we're given a life on Earth to prepare for eternal life when we leave here. Death of our earthly body is intended to be transition to eternal life in a new, sickness-free body. God's plan is for people to prepare for Heaven by believing that He wants them to go there, and living in a way that makes them ready for life in Heaven. He knows that's challenging but He helps us.
Christians talk about death quite a lot because it's the turning point where we either go to Heaven, or not, depending on choices we have made. To go there we have to tell Jesus we accept Him as Lord and Saviour, and try to live as He requires so that we will fit into the Heavenly way of life, which is based on love.
Our eternal life actually begins here when we accept Jesus. A relationship with Him is enormously life enhancing when we have faith. He wants us to feel joy, and to encourage other people in their faith and lives, and to tell non believers what they can have and how to receive it.