Dear eman1971:
Greetings. No, you do not have to prove sexual intercourse happened to win an alienation of affection lawsuit. Please see the following link to see what you must prove:
rosen.com/alienationofaffection/
Best of luck.
Janet L. Fritts
Attorney with Rosen Divorce
4101 Lake Boone Trail, Suite 500
Raleigh, North Carolina 27607
RosenDivorce.com
919-787-6668
The response posted above is based upon the limited factual information made available and is not intended as a full and complete response to the question. The only reliable manner to obtain complete and adequate legal advice is to consult with an attorney, fully explain your situation, and allow the attorney sufficient opportunity to research the applicable law and facts required to render an accurate opinion. The basic information provided above is intended as a public service but a full discussion with an attorney should be undertaken before taking any action.