They are very likely to take lengthy discourses into the latter as insensitive, obfuscatory deflections (and probably correctly so).

I would call the 'real reasons' typically given to be obfuscatory deflections. People seldom know the actual reasons for why they want to break up. More often they are explicitly aware of one of the downstream effects of the actual reason.

Which is not to say that descriptions of the biological eitology are not also obfuscatory deflections. Most answers to this question will be! In fact, answers to this question will usually be obfuscatory deflections because not to do so will necessarily be 'insensitive'.