The thought of losing those threads we are holding on to weighing us down, but we don't feel or see the weight. The past belongs in the past, and sadly we are inevitably going to lose people, things, and never get some answers. We can't let that hold us back though.
Sometimes the hardest choice really is letting go, and facing life front face forward. Things happen for a reason and while in can't speak for objects, and all answers, I can though for people. I'm pretty sure all people want you to continue on with your life and make it the best possible life for yourself despite them having to move on from you. They don't want to be tying you down holding you back.
Life will be full of moments it's honestly up to you to decide how you live based on them.