Well, your wife is not unusual. A lot of people seek the monogamous dream only to find it is not all that exciting and then long for that rush and excitement of being in love again. There is nothing wrong with that, but once you've created responsibilities in life the you have to deal with them and have a good measure of respect and consideration for them I think. Life is never the same again. Its grown up time.
Pacing is so important. Going at the pace of the one that is struggling the most is really important to poly success. As is time management; making sure their is a balance; spending equal time in different areas of life with the same energy and vigor. The biggest thing is to keep communicating with honesty and consideration.
Try doing a tag search here under "lessons" and "foundations" to get an idea of how to go about poly with some measure of success.
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