and to be alive consists in beholding God"
The above quote may sound like it came from the 1980's, but it didn't. More likely it came from the 180's. Ireneaus was one of the great thinkers of the early chruch (ca. 130-202 AD) More than 1,800 years ago, he articulated something we are still trying to grasp today: What does God want for us? What does God want from us? What is this life that I have been given and what am I supposed to do with it? How can I not end my life in disappointment?
The word, "disappointment" often is defined as 'sad' or 'grieved'. That is true as far as it goes, but it goes further than that. To be "dis-appointed" means to separated from, or miss, an appointment. It refers to missing an 'appointed' or expected event. Something I thought was going to (or, should) happen, didn't. I am disappointed. The grief and sadness are a reaction to the loss of what could have/should have been.
Disappointment is one thing when the 'appointment' is small (I didn't get asked to the dance, hired for the job, get the bike I wanted for Christmas, etc.). Then there are the big disappointments. What happens when you are disappointed with- miss the appointment of, your life?