a feeling or expressing regret or sorrow or a sense of loss over something done or undone
felt regretful over his vanished youth regretful over mistakes she had made
THE VENT If saying something stupid and regretful at some point in your life is now the standard by which we decide to fire someone then most would be unemployeed.
June 23, 2013 - Atlanta Journal-Constitution
Alex Rodriguez in Reuters I did take a banned substance. For that I'm very sorry and deeply regretful,Rodriguez told ESPN in response to a report in Sports Illustrated that he had been one of 104 players who had tested positive that year.
Chris Squire in International Herald Tribune Bassist Chris Squire, who formed Yes with Anderson in 1968, said Anderson's health was the band's primary concern, though he was "especially regretful of the fact that ...... many of our fans and friends have probably laid out nonrefundable airfares...