Previous next as images

Hi,
I’m using the advice from here https://www.ads-software.com/support/topic/add-next-and-previous-links-with-images?replies=9
to create image links for previous and next on https://www.talesofyore.com.
However, since this is a series of images, I’d really appreciate it if the previous or next image wouldn’t disappear once i came to a post where there are no more previous or next posts. Is it possible to do somehow? So that the image is actually fixed and the link on the image is created only if there are previous/next posts?
Thank you!