If two people cannot talk to one another and support one another through their struggle, then it seems to me that they do not truly have a relationship...they may have an acquaintance and perhaps, a friendship of sorts, but not a true relationship.
Each of us is responsible for our own choices and the consequences of those choices. Everything in life has risks, especially relationships. As long as both people are honest with one another about where they are in the relationship and what their concerns and worries are, then they can each decide for themselves where they stand with things and whether or not they can continue in the relationship.
Be very careful about presuming to know what is best for someone else in terms of possible harm without having talked about it with them, as that can lead to some very poor decision making and, perhaps cause you to walk away from a relationship that might actually be quite wonderful and rewarding for you.
Thank you so much for sharing your thoughts with me.