I'm just trying to consider an atheist point of view. You don't believe in God, so there is no objective morality telling you what to do. Thus you have no direciton, no objective "good" to be working towards. This is how atheism seems to me, as a Christian. I'm just trying to understand the line of thinking.
So you can say, I have nothing to live for other than momentary experience. But that is just hedonism, and it can lead to death. If you want to do coke nonstop and eat steaks, go for it. But it will kill you faster, and your body will suffer. We know these things, so we don't go 100% hedonist.
So we realize that we can relieve ourselves of possible future pain by making sacrificial choices. Thus we do not live as hedonists, purely for ourselves in the moment. I am not going to eat steak every single night so that I can do so once or twice a month and have it be a savory experience. There is no such thing as total freedom. We all make sacrifices to not do one thing in order to do another.
Now, all of that is fine, but what about our failing senses? As we get old, we lose our hearing, our sight, our memory even. Someone above thread was saying "What is the point of children, your grand grand children will not remember you" but this ignores the fact that you may not even remember yourself when you are older. Hedonistic experience can be fun what is the point of even doing these things if you can't remember them? For a materialist atheist, I wonder what the answer is?
This is where the value of having children and a legacy comes in for me. You do have some level of awareness. My grandfather passed away a few years ago and after having a stroke he spent several days in his bed with visitors. I was able to spend time with him and while he was unable to talk, he was responding to what me and my family were saying. He was there, with us, aware. He could not eat a steak or do coke, he could not even speak, but he was alive. IMO all life has a transcendent dignity that no material experience can provide. This is a big part of my faith in God. This is why bringing more life into the world seems like a worthy goal.