regretful
1. [ adjective ] having regret or sorrow or a sense of loss over something done or undone
Synonyms: sorry
Examples:

"felt regretful over his vanished youth" "regretful over mistakes she had made"

Related terms: unregretful
Similar spelling:   regretfully
  regret
  regrets
  regrettably
  regrettable
  re-create
  re-created
  Rexrode
  Rexroat
  recruit
  re-creation