Emotional affairs are affairs, period. Some people have a deeper connection in an emotional affair than a one night stand or purely physical affair, and your wife has every right to be upset.
Recovery from an affair take 3-5 years, and the burden to reconcile is 60% on the cheater's part, and 40% on the wounded spouses part.
http://www.survivinginfidelity.com/articles.asp
I posted a link to a great source, the Healing Library, from a great website that you can use to heal your marriage.
Specifically:
http://www.survivinginfidelity.com/healing_library/reconciliation/what-every-wayward-spouse-needs-to-know.asp
What Every Ws- wayward Spouse- needs to know
http://www.survivinginfidelity.com/healing_library/reconciliation/reconcile_musts.asp
What you must do to reconcile
etc
This is a great place to get info to heal your marriage.
If you cannot commit to the 3-5 year time frame, be totally honest with your spouse, and be ready to do 60% (at least) of the work, AND BE PATIENT while your spouse recovers from your cheating and betrayal, you should be honest with your spouse and divorce.