That might describe me, I guess. I'm not convinced that reality has any message or plot, as if it was a movie or a novel. It just is.
Yes. I'm not an atheist (though I probably am in your sense) but I am inclined to think that whatever meaning and purpose our individual lives have (or our societies collectively) are meanings and purposes that we ourselves give them.
That being said, I don't believe that all meanings and purposes are equally valid or good. In my native San Francisco many people seem to believe that fentanyl gives them meaning and purpose, as they turn themselves into living zombies. (With the loving aid of a government which seems to favor them doing it by enabling it.)
In my own case, I guess that philosophy gives me meaning and purpose. My purpose is to try to penetrate the mysteries (in full knowledge that nobody has and that I never will). Others find their meaning and purpose in love and personal relationships. Others find it in art or adventure. Probably most people pursue some combination.
I'm not convinced that there is any objective truth to which one we should ideally choose, though the fentanyl example illustrates that some choices are more functional than others.
Sociologists call that condition anomie. It's the erosion of any sense or morals and values, along with growing social alienation and breakdown of social bonds. My own opinion is that Western society is currently experiencing rapidly growing anomie, which explains everything from growing drug abuse, through skyrocketing crime, to angry and hostile political division, to the failure of schools to teach basics. It's social breakdown, pure and simple.
I think that societies can only function if shared things that draw people together are stronger than the divisive forces that push them apart. That's true even if the cohesive forces are largely mythical. In the past, and in some parts of the world even today, religion played that role. Other places a common culture played that role, common language, traditions, assumptions and shared sense of identity, all shared with one's neighbors.
And I think that our contemporary sense of cultural unraveling is due to all those cohesive cultural elements being under relentless attack.