What you are saying is that you personally want there to be some form of afterlife (you appear to prefer a cyclic one to a sequential one). You believe that life is purposeless without one.
This is like saying that buying a car is purposeless unless the car never wears out. That’s demonstrably untrue. A car gets you from point A to point B faster and cheaper than walking. That you have to replace it every few years is not some insurmountable problem that renders the car useless. Far from it.
Similarly, my life has purpose and meaning even if I do not think I will in some form live forever. I derive great meaning for example from helping my clients solve their software design needs. From helping my disabled stepson live comfortably and well. From leaving various legacies for my children and grandchildren to build their lives and aspirations upon. From any number of things.
In fact, I actually find comfort in the notion that life is finite, and has a beginning, middle and an end. If you really divorce yourself from the learned helplessness that religion instills in you, that you need salvation and/or eternal life, you can see that eternality could easily, in any of several ways, become its own hell.