If doing it for control purposes, he is using celibacy immorally.
It sounded to me like she wanted him to say he was going to marry her after 6 months.....6 months. If it was really just a "tiny little hint," then I would agree he messed up, but it sounds like it was more than just a hint.
No, the way I read it was that, after dating for six months, she wanted to go to the "next level". Since, with Mr. Washington, the next level isn't SEX, she wanted a commitment. An "If I stay with you and only you, and abstain until marriage, as you are doing, I need to know we're headed for marriage" sort of thing.
Six months may seem like a brief period of time to someone who's (cough!) in college, but once you're in your thirties and forties, women and men both tend to come right to the point a lot quicker. Time's a wasting, particularly for women who want to have children. And at that age, experience and wisdom should tell someone long before six months have passed whether or not they're wasting each other's time.
Or toying with someone else's feelings. A mature and virtuous man would not do that.