Well yeah even in week 2 when Janet lost her Grandad they showed her a small clip of that, but maybe Janet tried to be too brave and not show her emotions with that (which is good, instead of paying the sympathy card like all others have been doing).
This weeks VT was useless, and being fair to her, did you see some of them dresses they try to put on Janet? In 1 of them that black/Green thing she looked like a character out of a disney film

In the end she always goes on stage looking rather elegant though so she gets it right. What is the big deal with not wanting to wear certain things anyway? Them VT's are important for people seeing the personality of contestants and showing that made alot of people think, as u said, that she is grumpy and arguementative... when she seems quite far from that when she is live on air or on Xtra Factor, she just seems shy.