Cancelling marriage after ring exchange.death threat, suicide threat

Hello, I found a girl through matrimony and met her at her home. It was one week before I planned to leave for USA. Before I leave a ring exchange function was organized. It was a grave mistake from my part to consent to the function before talking long anough with the future partner. After communicating with the girl we both figured out that we are not a match. I decided to withdraw from marriage but girl disagreed. Now she gives me suicide threats and force me to marry. What to do now?