Dennis. This is a real question.
I'm 6'2" tall. Do you think that my height plays an important role in my "worldview"? That is, when confronted with reality in some way, do you imagine that I say "Hey, I'm sort of tall, I should react accordingly!"? Or do you understand that my height is normally irrelevant unless the situation involved bumping my head or ducking gunfire?
I ask because that is how relevant my atheism is to my every day life. I have merely removed the concept of god from my world and I look at it assuming there isn't one. But that assumption is not an active part of my thought process. I don't need it for anything unless I'm discussing the issue. It is a given, just like needing to breathe air, knowing that pigs don't fly and/or understanding the ineffectiveness of mistletoe when it comes to getting my ugly mug kissed. The information is there in the background, and available to me if I need it, but I don't confront the good, the bad or the ugly by remembering I'm an atheist before doing something ungodly.
When a tsunami kills thousands, I recognize that our planet can do some amazing and, in cases such as these, terrible things. I see the deaths as in inevitable by-product of such natural power, combined with everything from ineffective warning systems to people just being in the wrong place at the wrong time. I don't assign any evil the the tragedy. I see only unfortunate circumstances.
A school shooting, on the other hand, is a human being doing something to other human beings for reasons I simply can't comprehend. Yet any "evil" I assign to the act is merely me recognizing that the bad people involved were selfish SOB's with various mental and social problems that could perhaps have been addressed before the tragedy, thereby saving lives. So I see it as evil in the sense that someone was the opposite of good, but not evil in the sense that satan or original sin was involved.
No, life has no meaning. Other than what we humans assign to it. For our convenience or comfort. I've certainly done my share of assigning some sort of meaning to my life and the lives around me, but I don't for a second assume my POV to be absolutely accurate. It is part of the story I tell myself about living on earth. I'll get back to the story thing shortly.
Life events are indeed driven by chance, overall. Each of us are very lucky to be here, because it would have taken so little for any of us to not be born in the first place. Any change in history a few days or earlier prior to our conception would have either halted said conception or resulted, at best, in another combination go sperm and egg and we wouldn't be us. Right now I'm reading a history book about WWII, which took place before I was born. There were several instances where major naval attacks were planned but as the ships got ready to leave, people realized that it was Friday the 13th, and sailors consider it bad luck to embark on that date. So the ships left a day later, to avoid bad luck, and hence the battles ended differently. Victory might have gone to the other side, certainly different men would have died, and the whole course of history would have been changed enough that by 1950, when I was conceived, the odds of that specific egg and sperm getting together would have been unestimateably low. Since there is no god to know everything, my existence, and yours, was far from a given, even a few days before conception. Yet alone years before. If there is anything besides chance (and biology and a few other minor players), we don't know about it yet, and it probably isn't a major influence on existence. Things like gravity and the speed of light might have been influenced by factors other than chance, but once life got involved, chance indeed started to rule the day.
Morality is subjective. I wish it wasn't. I hope we can find a way to universalize and humanize morality so that young black men don't get shot and slaves don't get owned and soldiers stop killing, but there is a factor involved that prevents such an ideal world. And that is the humans that live in it, none of whom live by the same rules all the time. Stories are involved with here as well. Again, I'll get back to the stories in a minute.
I don't know that everything is comprised of matter (and energy, which is the same thing in a different form), but so far, it kind of looks that way. However, stories about gods and magic and wonders beyond all imagination have been a part of our human story for tens of thousands of years. This brings us back to stories. Which I shall now discuss.
All humans require stories. There is no way to exist on this planet and not have story after story in our heads explaining various aspects of reality. There is no requirement that any of these stories be accurate. They only need to be functional.
For instance, I have my own story about how American government works. It is simplistic, naïve, and inaccurate. I have never had access to good information about what goes on behind closed doors, about how big money influences politics, about what inspires a person to be a politician, about the general realities involved with governing millions of people, etc. But I've swallowed enough of the propaganda (democracy is the best way to run the world, we are a democracy, we are free, our country is great, etc.) and combined that with my own story and poof, I have ended up as a fairly decent, fairly well behaved citizen of my country, based almost entirely upon my acceptance of, and my manipulation of, a story that is totally bullshit.
And that's how humans operate. We tell ourselves stories about marriage and driving cars and the importance of our job and the relevance of entertainment and we put it all together with us inside it and poof, things seem to make sense. Even when they don't, in any accurate sense of the word.
And one of those stories often relied on is religion. Which is a story the provides a simplified view of reality, easily accepted, by the ignorant and the educated alike, so long as it matches their other stories, or influences their other stories, enough to seem plausible.
Little accuracy is available for any of our stories. No matter how much a realist a person is, they simply don't have enough information to ditch the stories and replace them with some accurate representation of reality. From time to time we have to face reality, like when a loved one dies or a partner wants a divorce or something, but most of the time we are all floating around in our individual fantasy lands, blatantly aware that our own story beats the crap out of most of the other stories, and humming along, erroneously thinking that we have our shit together.
I try to avoid the stories that are too obviously stories. Hence I'm not religious. That makes me an atheist. And I'm just as wrong as everyone else about everything else. But not about religion.
Everyone's worldview sucks. Most of them work. We would be better served if we all took it upon ourselves to add accuracy to all of our stories. We won't. And in the meantime, the religious want to stress the importance of their particular inaccuracies a bit more than I like.
That's my story, and I'm sticking to it.