To Capitalize or to not capitalize?

[Nia]

Hello everyone! My question here is this:

I have a monarchy system in my novel, and there is a king and queen yadda yadda. I know that when referring to them with the title, it has to be capitalized, for example, Queen Elizabeth. But if I am saying "the queen" while referring to a specific queen, would it then be "the Queen"? And does the same go for every title such as princess, duke, duchess, etc?

Or is the key just being consistent? Because I realize I refer to the Duke and Duchess with capitals, but when it comes to the princess, if it is not her full name and title (such as Princess Diana) I just say the princess.

Hopefully I didn't phrase this question too weirdly. It does feel weird to capitalize the Princess each time when not using her title, but I guess it is a proper noun. Just wanted to hear some opinions, I've looked it up and seen mixed reviews!

[Nicole Shantae]

Capitalise proper nouns but don't capitalise them when they're used as common nouns. So you're correct to say 'Queen Anne' and 'the queen'. Same as the duke, the princess, etc. don't capitalise when there's an article in front.

[David]

Hi Nia, Nicoles' advice sounds right. I had my story proof read/edited a while back and that is exactly what they picked up.

[Scott]

Sorry, but I think I disagree. The word isn't capitalized when referring to a common noun. He's a king among men. But when referring to a specific person, it is. Tonight, I'll be dining with the King. This may be specific to King and Queen and not other titles (such as the president) because the title is actually part of their name.

Would you like some tea, Your Majesty?
Tea would be splendid, my lord.