The moon changes appearance without changing identity.

Full, half, a sliver, gone: the moon is the same object throughout, lit differently by where it happens to be standing. Nothing about it has diminished on the nights you can barely see it. What changes is what is illuminated, not what exists.

On days when very little of you is visible, that is worth remembering. You are not a smaller person during a hard month. The parts of you that are not showing have not gone anywhere, and they will be lit again.