I have to admit, I have never been less interested in others. Last weekend I was walking around a fair with Polynerdist and thier son and there were a lot of "nicely" dressed women. I was a little taken back by just how disinterested I was in even looking. I seem to remember being much more distracted by this sort of thing in the past. I believe this is a result of my new awareness regarding the role of sex in my life. There is a huge standard set by the connection I have with Redpepper which makes the simplest sexual contact with her incredibly fulfilling. A kiss from her means more than the intercourse I have had in the past with some.
My "mono" friends find it hard to believe I wouldn't be chasing everything with a skirt due to the nature of my relationship. I remember thinking the same way when I was married and thinking about the idea of an open relationship or swinging.
In summary, for me, looking for an additional relationship would ultimately indicate trouble with my connection to Redpepper.
Now if I was poly, things would be much different of course