Richards, her father, her two young daughters and other family members kept a vigil at the bedside of Richards' mother, Joni, in a Long Beach, Calif., hospital for two weeks before she died.
The actress told OK! her mom's illness has inspired her to reflect on her own life.
"I was always a people pleaser," Richards said. "And I just finally got to the point in my life after having my daughters and going through a really ugly divorce (from actor Charlie Sheen), and ... my mother (being) sick with cancer, that I've just gotten to the point where life is so short and I just want to be happy."
Richards is the latest celebrity to mourn the loss of a parent in the past several weeks.