Othello and Desdemona

Write an essay answer in response to the following prompt:
Examine the relationship between Othello and Desdemona and explore what went wrong in this marriage.

Instructions:
Free feel to narrow down this topic in whatever way seems reasonable. Be as specific as you can in explanation pf how the work illustrated an important aspect of the theme. The essay should contain a thesis statement that indicates a conclusion about the issue tackled in the theme. The points in support of the thesis should be backed up with the evidence from the text.

Text:
Shakespeare, William. Othello. Ed. Brainerd Kellogg. New York: Clark & Maynard, 1892. Shakespeare Online, Amanda Mabilliard. 18 May 2014. Web. 15 April 2017.
http://www.shakespeare-online.com/plays/othellodp.html