So I'm an atheist but I wanted to answer with the meaning of life.
In the grand scale of things, it means nothing at all. It isn't even a blip, it's completely inconsequential. Your existence will have no lasting impact.
In the other hand, the atoms that make you will go on forever, and you will be reabsorbed, so to speak, and reused in a variety of ways, redistributed piece by piece.
When you die you will cease to exist. There will be no understanding of this because it is nothing. You will have no reflections, no contemplation, your consciousness will end. I suppose it doesn't help that I find that immensely comforting, I feel like I should not, because that lends to wanting it to be true, not using evidence.
On a very small, minute scale, the things you do do matter though. They affect the people around you and the world you live in. We do not live very long, so that's the important part for us. We can not properly perceive the time the universe has been around or will continue for, I am fairly certain it is not easy for anyone to wrap their brain around that kind of time. The meaning of life is what you make of it, it is what you want out of it, what you can get from it. My goal is to try to make life better for others, because seeing someone suffering, when we have so little time to exist in the first place, that's not right. Something good should happen for people before they are brought to an end. Because that is what will make their life matter.