I've taken some latin decades ago, but if I hadn't, I'd assume your book was sci-fi. I think you have to think of your title, along with the cover of your book, as the first selling points for your book. Who is your audience? Will they know what the title means or will they care? Would having an English title draw more or fewer purchasers?
Since you're book is a memoir, you've got more latitude with the title, in my opinion. I like the title, but I don't consider Latin a foreign language since it's no longer spoken. I see Latin as part of the roots of the English language.