I was able to disable this by changing the following lines of code in the bp-activity-classes.php file located in the buddypress > bp-activity folder:
starting at line 196 add WHERE component_name != ‘friends’ like so:
`if ( $limit && $page && $max )
$activities = $wpdb->get_results( $wpdb->prepare( “SELECT * FROM {$bp->activity->table_name_sitewide} WHERE component_name != ‘friends’ ORDER BY date_recorded DESC $pag_sql” ) );
else
$activities = $wpdb->get_results( $wpdb->prepare( “SELECT * FROM {$bp->activity->table_name_sitewide} WHERE component_name != ‘friends’ ORDER BY date_recorded DESC $pag_sql $max_sql” ) );
$total_activities = $wpdb->get_var( $wpdb->prepare( “SELECT count(id) FROM {$bp->activity->table_name_sitewide} WHERE component_name != ‘friends’ ORDER BY date_recorded DESC $max_sql” ) );`
