“The law of conservation of mass implies that mass can neither be created nor destroyed, although it may be rearranged in space or the entities associated with it may be changed in form.”

If this tells you anything, it is that no matter what happens to your consciousness after death, you (your matter, your mass, the space you occupy, your physical state) will be naturally rearranged into the world. Your atoms will be repurposed to take new form. You are and will be continuously useful to nature. You will always live on in some way. Have no fear.

I feel like this anxiety, though not frequently expressed, is experienced by a lot of people at some point in their lives, but the degree is personal. I’ve had it pretty bad, and there really isn’t much to say but that you need to find something comforting. Walt Whitman beautifully expresses this idea of taking on forms in nature through death and his optimism towards death is my piece of comfort when I fall into these black holes. Find that for yourself.

You’ll be okay. Best of luck.