She looks like this in public, wants to seem strong, because she doesn't trust anyone.
I agree with what you say in general, but I don't want her to SEEM strong, I want her to BE strong. Too many ''hard on the outside, soft on the inside'' female characters nowadays, I want someone who is tough on the inside too, but this is just my personal preference. That quote of hers ''I never NEEDED anyone, but I WANT you'' really got me, that is the kind of character I would love to romance.
Yes, this quote ...
I think that she will say "I need you" after many other events where she can make sure that she can trust the main character. After one day of dating, it would be strange to hear something else.
And yet, the quote can be interpreted in the literal sense, and in the sense that a strong Minthara does not want to show her real feelings because love is pain.
I think she is strong both inside and outside, but every strong person has his weak points, which only a select few know about. In the first act, the main character is not the chosen one, but the candidate on the long way to this