I found a great blog post by Sherry Amatenstein who writes for MORE.com and Match.com’s Chemistry among others. The post was in answer to a question about admiring and having a crush on another when in a committed relationship. Sherry’s response was interesting and entertaining. Read about it here if you want to find out why she thinks its good AND bad.
Sherry won’t say never to these types of questions, because even if you "go astray" (my words) it can lead to a deeper look and examination of your current relationship. I’m not so open minded. Yes, you could get a deeper look, but you could also ruin something good as well in the process. If you’re willing to take that risk – I guess that in itself makes a statement regarding your feelings for the current relationship right?
There are many idioms referring to this type of behavior which obviously must be prevalent enough to have phrases coined right? Here are two favorites:
The grass is always greener on the other side
You want to have your cake and eat it too
If you ‘ve got others, let me know!