One can think they are a cute couple and still be wary of thinking they are headed for marriage.
There are innumerable indications that suggest they are not necessarily a 'done deal', but having a gnarly back-and-forth conversation about that is pointless imo.
Well, the strong statement could be taken as just that: the press were making a private citizen's life unbearable solely because of affiliation with Harry. Seems reasonable to me to say something about that. If Harry hadn't (and doesn't in the future with anyone else) he'd be finding it very hard to date methinks.
All of Meghan's actions can be viewed as short term actions. None of them are irrevocable, and maybe she was already thinking of some changes. Who knows. I think she was getting some ugly stuff via social media, so shutting that down was an easy decision.
She could certainly be thinking of moving to London to live-in with Harry. Such a move does not presage marriage necessarily in my book. It's also a good career move on many levels.
As for the Invictus Games, that was clearly a show, yes. Unusual, in fact. More for Harry than for her, I think. He's the one to watch. Meghan is saying yes to an adventure. I'm with her on that. But marriage? If I were her girlfriend I'd caution great care, go slow. This is a situation that may not be what it seems. That's what I'd caution and she'd then do what she wants.
I think Harry is looking at marriage as the end goal.
He is doing all he can to win her. But how far Meghan may be willing to go at this point, well, we'll be finding out. 20/20 is always superior.