Why does it matter so much to atheists that God doesn't exis...

Because these are not any gods rules we are talking about.

Those rules that you are trying to reinstate are rules made by men who didn't know anything about the earth, nor anything about all of the other inhabitants of it. How can you not see that?

THE BIBLE IS THE PROBLEM!

Why do I feel so down and not happy anymore? I also feel really tired and non-motivated. Is that normal for someone to feel that way?

I am speaking to the US Bible thumpers here, of course ~ many of whom are flat-earthers who deny evolution and see scientists as evil people who are constantly trying, and succeeding, in disproving their beliefs one by one.

And how do you deny hundreds of years of advancement in all fields of science?

The people of the modern world have evolved past all of that nonsense.

How would you feel if your friend confided in you that she is cheating on her husband, knowing that he loves her deeply? What emotional and ethical considerations would you grapple with in response to her revelation?

These are man made rules - made thousands of years ago for the use of the humans who lived thousands of years ago.

And then use and ENJOY these fantastic scientific advancements every single day of your life?

I do not personally care if you believe in a god or not.

What are the ten cars that make me no longer feel inferior?

IT does not matter, mainly because it does not exist.

Notice that I said their rules, not any gods rules.

A belief in a god is not the problem.

What are some interests in sharing pictures of wives?

My problem is that people who try to shove their rules down everyone's throats - including by physical force - DO EXIST .