See, this is the true struggle here. Madoka does feel like an explanation would clarify things a little here, especially after such confusing statements. On the other hand.. she can't exactly imagine that a life where half of him died has been very kind. And it's not like Madoka wants to make Piccolo think back on sad things from the past..

So she doesn't answer immediately. Instead her eyebrows knit together in thought and she slightly bites her lower lip.

Rather than asking for an explanation what Madoka settles on saying is just:

"I'm sorry, mister Piccolo.. You must have had a hard time."