Denise Richards thinks she is "too old" for Charlie Sheen.

The 39-year-old actress is pleased she is on good terms with her ex-husband - the father of her daughters Sam, seven, and six-year-old Lola - following their divorce five years ago, but she insists they would never get back together.

She said: "That door is closed. I think he and I are better as friends and having our daughters. I'm way too old for him now. I'm way past his age range."

Charlie - who also has two-year-old twin sons Bob and Max with ex-wife Brooke Mueller - has hit the headlines with his wild and erratic behaviour this year, but Denise admits she initially fell for him because of his "strength and courage" in sobriety.

She told TV talk show host Piers Morgan: "I have a different perception of my relationship with my ex-husband than what was really happening. And when we fell in love, he had been sober for three years. He was, you know, getting his life back together. He'd just gotten a job on 'Spin City'.

"And I really admired his strength and courage for overcoming addiction and being so humble about it. And that's what attracted me to him. So the Charlie that some of you have seen over the last six months is not the person that I met and married.

"He was amazing. He was so humbled and sweet and charming and funny and had such a great heart, and very honest. And we just had a very deep connection that we had together."

The 'World is Not Enough' actress - who also has an adopted one-month-old daughter, Eloise - admits she has to take relations with 45-year-old Charlie "a day at a time", but is pleased they get on well for the sake of their children.

She said: "I take it day by day. One day at a time.

"I think it's not about he and I truly. It's about the kids.

"His lifestyle's his lifestyle. And I've learned to accept it, even if I agree or don't agree with it. It doesn't matter. So times where things are very calm and cordial with us, I really relish those times, because it's so much better for our kids."