If in Christ we have hope in this life only, we are of all people most to be pitied. (1 Corinthians 15)
I think that it is safe to say that many Christians, if they were to stop and think about it, would say that it would be okay if there were no heaven after this life. They would say this life can be good enough - even if there is no more. I am not among them. If there is no new heavens and new earth, if there isn't the resurrection of the body and the life everlasting, if what the Gospel promises me for later is a fraud, then my life is a waste of my time. Eternity with Jesus as a perfected person enjoying all the other saints is the justification I give myself for the disappointments, struggles, heartbreak and loneliness of my life. I'm not saying that life for me now is horrible. It isn't. There are lots of good things to enjoy, and I do enjoy so many of them. But the enjoyment of those things cannot make up for what I lack, what I was made for, what I long for. And the only place where I will be able to experience any of that is as a renewed person in a renewed creation. If there is no resurrection of me and all of this, then I should be pitied for so many of the choices that I have made as I have tried to follow Jesus. And the Apostle Paul agrees with me.