Most people want to live meaningful lives. They want to live lives that are worthwhile and fulfilling. But what makes life fulfilling and worth living? What makes life meaningful?
For some people, religion does. Or at least it plays a significant role here. Other people, like me, can't find any meaning in religion because they can't believe in it. So does this then mean that people like me can't have meaningful lives? Are our lives doomed to meaninglessness because they don't include religion?
Not at all!
Life without religion can be meaningful. Indeed, it can be very meaningful.
Meaning in life without religion can be found in the many familiar, meaning-conferring elements that aren't religious in nature. These include friends, family, romantic love, pets, good careers, personal projects, learning, teaching, noble causes, helping others, striving for moral excellence, notable achievements and experiences, hobbies and recreational activities, and so on. There are many non-religious sources of meaning in life, and it's in virtue of such things that life without religion can be meaningful.
"Religion doesn't have a monopoly on providing a sense of purpose in life."
It's also worth noting that life without religion can have purpose. We surely do need purpose in life in order to have a meaningful one; it's hard to imagine having a meaningful life without having a sense of purpose in it. And religion, of course, can provide such purpose for many people. Nevertheless, it would be a mistake to think that religion is needed for this purpose, or that it's the only thing that can provide such purpose.
Religion doesn't have a monopoly on providing a sense of purpose in life. Instead, we can give purpose to our own lives. Taking care of our loved ones, helping needy humans or non-human animals, fighting for good causes (e.g., freedom and justice), striving for moral excellence, contributing to science, music, literature, art, or other areas of enduring human culture -- such things can provide the non-religious with a sense of purpose in life.
It's worth noting, too, that life without religion can be meaningful and have purpose even though it's not lived for the sake of getting into Heaven or some other desirable afterlife. Trying to get into such an afterlife may indeed provide some people with meaning and a sense of purpose in life. However, trying to secure one's own place in a desirable afterlife isn't necessary for having a sense of purpose in life, or for having a meaningful life, because life without religion can be rich in the non-religious sources of purpose and meaning in life already mentioned.
"Our lives will end permanently some day ... All that matters is what our lives are like while they last."
Finally, it's worth noting that our lives needn't last forever or look significant in the grand scheme of things in order to be meaningful. Even though our lives don't last forever and may look utterly insignificant in the grand scheme of things, they can still be meaningful by containing a healthy amount of the meaning-conferring elements outlined above.
Our lives will end permanently some day, and they might seem insignificant in the grand scheme of things, but these things don't matter when it comes to having meaningful lives. All that matters is what our lives are like while they last. What matters is what we have, and what we do, and how these things affect us.