I've met women women who have had those sorts of tantrums about getting married. They did not need to be medicated because of one nutso event.

You can never ever push anyone into marriage. It is a long term commitment - life long, both parties need to be really sure - and that can take years. Whats the rush if he does want to be with you? Do you need a green card or something? Pushing him into it is far more likely to result in ending it early. Marriage does not guarantee that he will stay with you, especially if these kind of tantrums are a regular occurrence.

Have you ever thought about doing DBT? This could be beneficial to you.