Often times i've seen people who were about to say something and open up, but because the other was too quick to say something out of assumption, they fold up and keep sealed lips.
The best thing we can do is listen. And we listen by been sensitive, reading the signs, body language, the moods, etc.
By not been quick to compliment someones strength for haven survive something, and allow them the chance to express themselves, they just might open up and let you know how difficult its been trying to appear strong.
But when we compliment without properly listening, they might just close up and continue to pretend to be strong.
I really love the point you made here.