Something I’ve struggled with for a while now... I’m sure there is plenty of philosophical thought devoted to this  idea which I have yet to find. I’m sure this is not an original idea. But nonetheless, it blows my mind.

You can’t change the past, and it is the past which has formed your present. You don’t know the future and how your decisions will affect it, all you can do is guess the outcome, and that guess is based on things that have already happened and cannot be changed. 

So really you are just on a ride, experiencing. 
Your decisions aren’t really yours, they are determined by everything that has happened in the world, before the moment they were made. 
Everything you will go through in life has really already been determined, before you were even born. 

The experiences you will have, people who will shape you, ideas that appear to you, decisions you make, mistakes you will regret, emotions you feel, success you acheive. None of it was really because of you, it was just you who experienced it. 

Even gratitude and appreciation of this is not a decision, it is itself an experience. If there is a point of life, it is to experience. And if there is something after this life, our experience here is all that will matter there. 

 Another way to look at it:  from an objective, scientific perspective - the perspective we would ordinarily seek to determine or state any truths about the world - the concept of "now" has no meaning.

There is a dimension of time with a series of values etc but none of those values has any particular privelege over any other.

So the concept of "now" is entirely subjective - it exists only in our minds (well in mine actually).

It follows that past and future are equally meaningless, objectively. 

 That’s an interesting one!