Xien_Rue:
The first thing she must do is drinking medicine to make her sterile. Married to someone you don't love is something. But voluntarily give birth to that man child is another thing entirely. A child will in a way bind you forever because he is the result of the union.
When she gave birth to a baby, that would be never ending process, she would never have to be with her lover.
Once their relationship cut off like this, even when the time she becomes a Regent, they shouldn't get back together. If they would, I would probably drop this.