I receive a number of inquiries about how to stop an emotional connection from deepening once it begins. Here is a previous post on the topic.
The Growthtrac blog has some wonderful resources to help a marriage. Sheri has scribed the post, When Does It Become An Affair. In this post she goes through how a relationship progresses to an affair. She mentions sharing intimate feelings and details and then being hooked and thinking about the other person just about 24/7. This squares with my experience and also here where I shared how emotional affairs begin.
Bowden left an insightful comment on Sheri's post, "When does it become an affair? When secrets are kept from your spouse. The difference between an emotional affair and a friendship is the truth--the whole truth--in a timely manner with your spouse."
It is difficult to tell your spouse when you are starting to feel that attraction to another. One of the best ways to burst the bubble of the illusion is go to your spouse and say, "I need your help. I'm developing an attraction with somebody at work. I don't want it to go further because I love you and I value our marriage. Let's you and me set up some parameters for this relationship." No outward parameters will matter if you don't guard your own heart.
Obviously, your spouse will want to process this bit of information. Be forthcoming will all information. This helps keep you accountable when a temptation monkey jumps on your back and says, 'it won't hurt anything to have lunch with...' and helps your spouse keep trust in you which allows you to maintain emotional intimacy in your marriage.