One of the most well known church prophets stated that he would rather see his own burbank hook up dead in their coffin than married outside the temple. But realistically, if she fo not open minded enough to even listen to someone who has a contrasting view dzting the church - how will she not continually discount you and your lack of beliefs.
How am I certain. It MAY be true that she will not marry him unless he converts.
Know her limits on substances.