Mary Astell was an early feminist. She believed in the intellectual equality of men and women, and felt that marriage was essentially demeaning to women. Not completely unlike an underlying sentiment of today. Is that not the premise for complaining about your spouse? You think you are being demeaned by them. You think you are better than them.
I find Astell's choice of words quite telling when considering the female's undertaking of marriage. "Martyrdom" says it all, hence the reason she never married. (Did you also catch the "brute" comment?)
Now I can honestly say I am no expert on the topic, but can tell you that if you go into marriage with a skewed idea of what it is to be, you will be genuinely unhappy. At the end of Astell's essay, she does, in essence, say that women need to be thoroughly educated in their identity as well as various studies before marrying, as to make a sound choice. I could not agree more.
Understanding (first) who God has made you, what God expects of you in marriage, and lastly your expectations of marriage are essential in finding ultimate satisfaction in marriage. Notice I didn't use the word "happiness". Happiness is subjective, as it is often equated with an emotion that is quite simply fleeting.
I find value in hearing out other views of marriage, and find even more value in watching the way in which the theories conveyed are played out in ones own life. I respect Astell all the more as she did stay true to her feminist viewpoint of marriage in abstaining from it.
For those of us who are in the midst of the most wonderful adventure we are capable of, let us make the most of it. It is neither "strictly business" nor "pure passion". It is a living, breathing entity. It needs to be tended to and cared for each moment of each day. Do you resent your children for needing food and clothing? Why should you resent your spouse for needing you?