Pagination per month with custom date field

I’m trying to understand how to make a custom pagination.
What I need is this:

< January >

I have posts under the category ‘news’, so I have to show them with pagination.
I get the month from a custom field called ‘event_date’.

I need that when the user clicks the arrows, the pagination shows the posts of the next/prev month, and the text changes for that month.

Any help will be so appreciated!
So far I got this:

<?php
$args = array(
'category_name' => 'news',
'posts_per_page' => 20,
'paged' => $paged
);
$temp = $wp_query;
$wp_query = null;
$wp_query = new WP_Query();
$wp_query->query($args);
?>

<?php while ($wp_query->have_posts()) : $wp_query->the_post(); ?>
<li>
<a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></li>
<?php endwhile; ?>
</ul>
<div class="navigation">
 <div class="alignleft"><?php previous_posts_link('&laquo; Previous') ?></div>
 <div class="alignright"><?php next_posts_link('More &raquo;') ?></div>
</div>
<?php $wp_query = null; $wp_query = $temp;?>