Keep them mentally healthy in general, and keep an eye out for latent problems. People deal with cheating boyfriends all the time, but when that's added to other mental health issues things can go very wrong very quickly. In this case, the sudden life changes seem to have left Katie off balance and vulnerable, and when the article refers to "perfectionism" I suspect that's a reference to some underlying mental health problem.

Note that there's a fine line between pathologizing normal personality variations, and missing real issues.