The British program The National Wedding Show commissioned a survey of married couples in that country. They found that, on average, a couple got engaged nearly three years after they met: two years, eleven months, and eight days, to be exact.
The survey also found that she wished that he had proposed sooner -- four months sooner, on average.
I have met many couples in which she was waiting, with decreasing patience, for the proposal that she knew was coming. In fact, he often delays the proposal just because she is expecting it. He wants to surprise her. And he doesn't want to feel like he is following orders.
Still, if four months of grief can be avoided, or even cut back to two, many couples might have a happier life.