When you experience trauma for the first time, you are alone, but when you re-experience that event (through memory), you find out you aren't actually alone, past-you and present-you share that burden

Similarly, future-you is also looking back at this moment, you aren't alone. You are a 3-dimentional creature and you perceive time linearly, but somewhere, outside of the boundaries of space-time a version of you is with you right now, watching you, accompanying you. Similarly, a past version of you, the childhood spirit of innocent and of hope, is alone traversing this journey, together.