Anotherconfused, I wouldn't be too hard on yourself. You have not been faithful in terms of the bounds of your marriage as it seems that a kiss or two and fantasy talk are out of bounds, but you are in no way in a position to regret having sex with the man. You know it wasn't right and now don't do it again.
I don't see any problem with you starting the conversation about poly in terms of generalities. Give yourself a break on the kiss/whisper thing and use it as a learning tool for what you think you might want in the future. Market it to your hubby as such and start talking.
Ask him if he really is uninterested or is just nervous about it and why? Perhaps its a can of worms he doesn't want to open right now and that should be respected. You could tell him that you can wait, but will be bringing it up again in a set amount of time, because it is important to you... This way he will have time, can learn a bit perhaps on line or elsewhere, and can be ready for the talk. Maybe this will be of help to him... think of who he is as a person and then ask. Don't assume you know how he will be or has been because of past actions. Ask... might as well start with some good communication. You will need it anyways if you go down the poly path.
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