URGENT: Website down following update of Divi theme

Hi there,

I've just updated the Divi theme on our WordPress site, and now the site is down. When you enter our web address, the following error message occurs:

Fatal error: Allowed memory size of 41943040 bytes exhausted (tried to allocate 90 bytes) in /home/angelabusuttil/public_html/wp-content/themes/Divi/includes/builder/class-et-builder-element.php on line 171

Is it possible to uninstall the update? Or can you offer any other advice to sort this out?

Thanks very much for your help.