this is completely up to opinion ofc, but I don't think maria was the strict one. She was probably religious, because why not, but like you said, she did have to illegitimate kids with a pagan god (whether he'd be considered satan tho, I don't think bc usually monotheistic religions aren't very comparable with polytheistic ones, and hades is also the ruler of elysium so he would be both god and satan)
maria's dad was a diplomat, so he was rich and likely a socialite, at the time maria would have nothing to her name and very little money that was hers alone, she was probably supported by her family (read: her father), who would have been strictly catholic (or at least appear to be so in mussolini's time), and who would've covered up her two bastards with some sob story of elopement gone wrong or something of the sort
not to mention even "liberal" people back then had lots of issues with lgbt people, and even if they didn't they wouldn't have often supported them openly, since fascist regimes aren't known for their open-mindedness