To melt one's heart

Joanna was an ordinary young lady. Just like how other young ladies would normally act, she would apparently be affected by such a sweet compliment that came from a gentleman, especially when it was the first time she heard a gentleman, who was not her father, praise her as a beautiful lady and the only one in his eyes.

Moreover, there was no suitor who ever said that to her.

However, Joanna was in a situation where she could not act normally, as she should, in response to the compliment she heard.

If she was really a normal lady who had never experienced a nightmare that haunted her life since then, she would have probably jumped here and there in joy with a blushing, happy face when hearing a man praise her for the first time in her life.

Therefore, she refrained from being overjoyed, which would make her guard down, as ending up like Joanna in the dream was the thing that Joanna avoided.