That seems quite specific enough. I can't think of what you could narrow it down to. You could write an essay of any length on that topic.
Naturally, it would be best if they loved each other. But if you've chosen to rule that out, it's quite a good simple topic. But you say, I think, that you are not sure how to discuss it. In that case, why choose it as a topic?
Do you have the life experience or the opinions to deal with this topic? What do you think is better and why?
Student or Learner