>19-year-old women and 45-year-old men are adults free to decide to do what they want. If they choose to do something you disagree with, others disagree with what you do.
The president was actively betraying the trust of his wife and family, so in fact it wasn't as libertarian as you make it seem.
Beyond that, the memoir clearly shows massively inappropriate behavior for a sitting president or anyone with such a power disparity, to include significant instances of coercion and actions which denigrate the position and shame the relationship he had with his wife.
Shame on you for equivocating.