Next/Previous Issues

I’ve taken over an organization’s WP site and I’m trying to clean up some of their code. However, some of it is structurally unorthodox. One issue I’m having is with Next/Previous navigation. It appears within the loop on the main index and doesn’t appear on the individual posts.

If I move the Next/Previous section after the endwhile, the whole thing breaks. However, putting test text after the endwhile gets it where I want it (at the end of the multi-post index and below the comments on individual posts).

Please note that this site (so far) is NOT using single.php.

Here is the code of my index.php file:

<?php get_header(); ?>
<div id="body_innergreen_container2" class="full-width">
	<div id="wrap">
		<div id="top_menu">
			<?php wp_nav_menu( array('menu' => 'Restructured Menu' ) );?>
			<div class="clear"></div>
		</div>
</div>
</div>

		<div id="container">

			<div id="middle_container" style="width:731px; margin-top:-10px;">
				<?php while ( have_posts() ) : the_post() ?>

					<div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
						<h2 class="entry-title"><a href="<?php the_permalink(); ?>" title="<?php printf( __('Permalink to %s', 'your-theme'), the_title_attribute('echo=0') ); ?>" rel="bookmark"><?php the_title(); ?></a></h2>

						<div class="entry-meta">
							<span class="meta-prep meta-prep-author"><?php _e('By ', 'bbf'); ?></span>
							<span class="author vcard"><a class="url fn n" href="<?php echo get_author_link( false, $authordata->ID, $authordata->user_nicename ); ?>" title="<?php printf( __( 'View all posts by %s', 'bbf' ), $authordata->display_name ); ?>"><?php the_author(); ?></a></span>
							<span class="meta-sep"> | </span>
							<span class="meta-prep meta-prep-entry-date"><?php _e('Published ', 'bbf'); ?></span>
							<span class="entry-date"><abbr class="published" title="<?php the_time('Y-m-d\TH:i:sO') ?>"><?php the_time( get_option( 'date_format' ) ); ?></abbr></span>
							<?php edit_post_link( __( 'Edit', 'bbf' ), "<span class=\"meta-sep\">|</span>\n\t\t\t\t\t\t<span class=\"edit-link\">", "</span>\n\t\t\t\t\t" ) ?>
						</div><!-- .entry-meta -->     

						<div class="entry-content">
							<a name="content"></a><?php the_content( __( 'Continue reading <span class="meta-nav">&raquo;</span>', 'bbf' )  ); ?>
							<?php wp_link_pages('before=<div class="page-link">' . __( 'Pages:', 'bbf' ) . '&after=</div>') ?>
						</div><!-- .entry-content -->

						<div class="entry-utility">
							<?php the_tags( '<span class="tag-links"><span class="entry-utility-prep entry-utility-prep-tag-links">' . __('Filed under ', 'bbf' ) . '</span>', ", ", "</span>\n\t\t\t\t\t\t\n" ) ?>
<br><br>

							<span class="comments-link"><?php comments_template(); ?>
</span>

						</div><!-- #entry-utility -->

<?php global $wp_query; $total_pages = $wp_query->max_num_pages; if ( $total_pages > 1 ) { ?>
						<div id="nav-below" class="navigation">
							<div class="nav-previous"><?php next_posts_link(__( '<span class="meta-nav">&laquo;</span> Older posts', 'bbf' )) ?></div>
							<div class="nav-next"><?php previous_posts_link(__( 'Newer posts <span class="meta-nav">&raquo;</span>', 'bbf' )) ?></div>
						</div>
						<!-- #nav-below -->

			<?php } ?>

					</div><!-- #post-<?php the_ID(); ?> -->
				<?php endwhile; ?>

			</div><!-- #content -->
<div id="right_container" style="margin-top:-20px; padding-right: 10px; background: url('https://www.hoffmaninstitute.org/wp-content/themes/hoffman/images/body_inner02_bg.gif') repeat-x;">
  <?php echo do_shortcode('[RegularRightSidebar]'); ?>
</div>

		</div><!-- #container -->

<?php get_footer(); ?>