The 'Maggie May' singer dated former Bond girl Britt for two years from 1975 to 1977 and he admits when they were first together the pair used to enjoy a passionate sex life.
He said: ''We were very intimate, very quickly. Within a week, I knew I was falling in love. In the early heat of our relationship we spent a lot of time having sex in a Malibu beach house that belonged to another former husband, Lou Adler.
''Later, during enforced spells of separation, Britt would send me love notes in packages that often contained a pair of knickers.''
Although they enjoyed a very racy relationship, Rod claims the pair were very romantic with each other and she taught him about the world of art.
He said: ''It was a genuinely romantic time. She knew about paintings and antiques. I prided myself on having an eye, but I didn't really. It was Britt who taught me how to look.''
However, when the relationship turned sour, Rod began to ''drift off'', proving to him even being with the world's most beautiful woman would not necessarily make him happy.
Writing in his autobiography 'Rod', currently being serialised in the Daily Mail newspaper, he said: ''I started drifting off, just disappearing and not coming home, only to find Britt waiting up and asking, 'Where have you been?'
''Britt thought that she and I were headed for marriage. Yet I knew all along, deep down, that I wasn't anywhere near wanting to settle. And when that became apparent, it really hurt her.
''Which I suppose servers to illustrate that you can be with one of the most beautiful women in the world and still be an ass.''