You're The Big Cheese

Happily single: I have no reason to question that, nobody else gets to decide how you feel, and I'm happy for you.

Happily dating: Kind of weird that you'd feel the need to clarify. You know you don't have to date someone who doesn't make you happy, right?

Happily engaged: Same as previous, but more so. You know you should not be getting married to someone who doesn't make you happy, right? I'm not leaving before I know that you know.

Happily married: Could go either way tbh, but most likely you are. If someone's not actually happy with their marriage, it shows, no matter what they say.

Happily divorced: Yeah this one I have no reason to doubt. Nobody says they're happy about being divorced unless they really are happy about it.