You can use a filter to pre_get_posts so that only your posts are listed. Something like this:
function my_posts_only( $query ) {
global $pagenow;
if ( 'edit.php' != $pagenow || ! $query->is_admin )
return $query;
if ( ! current_user_can( 'manage_options' ) ) {
global $user_ID;
$query->set( 'author', $user_ID );
}
return $query;
}
add_filter( 'pre_get_posts', 'my_posts_only' );