The inclusion of the first two letters following the novel give a little more insight as to why Catherine Earnshaw chose to marry Edgar Linton instead of Heathcliff, aside from her simply being a semi-miserable human being. Because men held so much power over women, and essentially were in charge of their finances and standing in society, Edgar was the better choice for marriage. Catherine tells Nelly that one of the main reasons she loves Linton and wants to marry him is because he loves her. His love for her gives her some reassurance that she will be treated well. She believes that he will not leave her for another, or mistreat her, and will provide for her and their offspring. Judging from the fact tthat his rewinds to her giant temper tantrum is to propose, we can assume that there isn't much he won't put up with from her.

Heathcliff, on the other hand, is an unknown entity. His temper is so volatile, that Catherine cannot be assured of his continued affection for and patience with her. He also at the beginning of the story, has nothing to offer her but his possibly fading love. Since Hinley is the heir to their father's estate, Catherine has no real assurance of continued fortune. Edgar offers her stability and security, both in love and money. Later, we do see that his love for Catherine has not faded, so she may have misjudged him on that. However, given how the unrequited nature of his love has twisted it and him into an ugly, vengeful thing, we also believe that she made the right decision on spouses.

Because women had so little power, Catherine asserts hers in the only way she can: she chooses the husband who will guarantee her a secure future. Edgar is capable of the kind of unselfish love that was rare, and for which Heathcliff does not have the capacity. This love of Edgar's gives Catherine the peace of Mind that she will be taken care of no matter what, as will her offspring.