Actress Charlize Theron considers herself `very lucky" to be engaged to actor Sean Penn, but still finds the concept of marriage "strange".

The 40-year-old told Esquire magazine that Penn, 54, makes her heart skip a beat and she is madly in love with him, reports femalefirst.co.uk.

Theron -- whose mother shot dead her alcoholic father after he attacked her while drunk -- said: "The marriage thing is always so strange to me anyway. I love the possibility of anything, but I'm really enjoying myself and the everyday moment and how that coincides with my son and my life and my friends. I'm a very, very, very lucky girl. Very lucky. He's hot. He is hot. How do you say that in an interview?

`You're a 40-year-old woman sounding like a 16-year-old. There's something beautiful about that, but you lack the articulation of really saying what it's like when somebody walks into your life and makes you see something that you really never thought you'd be able to see."

The couple are expected to marry this summer. While the nuptials will be Theron's first, Penn was previously married to Madonna from 1985 to 1989 and Robin Wright from 1996 to 2010.