Rules and boundaries are very important when you start out. There is no doubt about it, its hard work! We all have had different degrees of that on here, be rest assured. Its important to remember that things change as you go along. Your rules should not be set in stone. They need to be changed as you go along and experience each new aspect of this journey. I don't think its unreasonable to ASK that he hold off on pursuing a romantic connection with this woman you saw an email from. You can't MAKE him, but you can request and he can say okay or not.
Often there is a time limit that involves having processed how you feel about stuff. Perhaps one day you will feel okay about his contacting her again.
As with the bed thoughts? Ya, you are no where near ready to start a poly relationship dynamic if you are giving him the ultimatum of not ever being sexual with him again if he dates other women. It might be best to sit and figure out your common goals together. Do you even have any? If you do, then great, you can begin baby step rules and boundaries. If your goal is to have his undivided attention and you can see no other path, then perhaps its time to let him go. Maybe not right away, but plan for that inevitability. We have a friend that is in a mono relationship. They know it will end one day but enjoy what they have right now.
As for what you could be doing while he is occupied (and you will find you will have a lot of free time)? You could be spending that time taking care of yourself. Treat yourself, better yourself, volunteer, read self help books, visit friends. Get used to your time and become independant rather than co-dependant. If it doesn't work out you will be better for it and if it does your will be better for it. Its win-win.
Last thoughts... Read lots on this forum. There is a lot of info that will be helpful. A lot of common thoughts and stories. Also remember to take your time. There is no rush and each step should be well exhausted before taking the next step. In no time poly life becomes very complicated and emeshed. Its best to be fluid with communication honesty as soon and as often as you can. Best to start practicing that right away in the context of starting off slowly.
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