If you don't believe me all you have to do is look at the ratings or read through the reviews to see how loved this show really is! She was married to Gabriel Byrne in 1988 and they divorced in the year 1999.
Is it enough to get the series renewed, who knows? She had her most high-profile role in quite some time in 2007 when she was cast in Ocean's Thirteen.
Season 5 has been taken over by a witless David Lynch wannabe, this series is thus destroyed from within and I doubt we'll see a season 6, as if anybody will care by then.