We are wistful about the golden days of the past and dream of a distant future unclouded by necessity. But I suspect that if our inner souls were asked what in life they really missed, the answer would be primal danger and stress.
So, how do you get back to heaven? To begin with, just notice the thoughts that take you away from it. You don't have to believe everything your thoughts tell you. Just become familiar with the particular thoughts you use to deprive yourself of happiness. It may seem strange at first to get to know yourself in this way, but becoming familiar with your stressful thoughts will show you the way home to everything you need.