Really sorry to hear this, James!
Do any errors pop up on your site if you head to your site’s wp-config.php file and change this line of code:
define('WP_DEBUG', false);
to this:
define('WP_DEBUG', true);
That will display PHP errors if any exist, which might be quite useful here. So, make this change, then review the white blank page and see if any error text is there.
In the meantime, to share login information or other sensitive details, just check the “Set as private reply” option before posting it as a forum reply to this thread. If you check that option, the reply will only be visible to you and to us on the support team.
Cheers,
George