So i am assuming you are rational & logical person. I agree with you that you can't just stop overthinking, i do the same for many things, but for ultimate objective of life you have to explore things deeper to find true meaning of everything. Same like butterfly effect, everything plays at-least a little part for something bigger, so your life is not meaningless at all, it does contribute to something. I also went through phase of hollowness which you are facing, i tried exploring human nature, divine books, science books, nature etc but i am at peace now. I cannot suggest an easy solution or easier path right away because everybody's struggle is different, so I suggest you to do the same to dig deeper.