Well, you have not heard one of my sermons
.
I agree with you, to a degree at least. God did not promise us happiness. And there is happiness without God, we see it all the time. What is missing is peace, freedom from the wages of sin and the relationship that all of us were designed for. But there is no promise of wealth, health, happiness or anything so carnal as that. God made one thing very clear, flesh is flesh, spirit is spirit.
Truth is truth, no matter what we might think or justify to ourselves. We can say the sun is not rising and continue to say it all night long, but saying it means nothing in the morning. The truth is rising.
All you have to ask yourself is this: If there is a God and He can be known in a personal way; what should I do, how should I respond to Him?
You can hope you are right about life and simply use observation and such to justify your views, however; suppose there is a God and He's is trying to draw you to himself. How do you make that go away?
You can use words constructed of poor theology and understanding spoken by preachers as justification of a world view. But the truth still stands as true.
If God exists, and He's trying to draw you to Himself what have you observed and experienced that can make Him not exist?
Read these:
Romans 3:23, 6:23, 10: 9and 10.
God bless you on your journey.