Hi Nolonger,
Is there a little voice inside your head telling you there is something a little messed up about wanting to go back to a woman who cheated on you with a fellow JW when the two of you were practically newlyweds ? She's now living a debauched life (from a JW standpoint) yet will only take YOU back if YOU return to the religion SHE has been expelled from ?
If so, listen to that voice....it's your subconscious reminding you of what you what you already know. It sounds like she is another casualty of the JW religion who still believes it's "The Truth" on some level and is acting out her self loathing by doing things that are ultimately damaging to her. Right now you are in the grieving process which is no time to make any big moves just to relieve the pain your undergoing. I'm sure there's more to the story but so far I see red flags all over this situation.She cheated on you and is disfellowshipped so why is she calling the shots?
Have you gotten counseling or has she ? It might be a good idea to have a professional help you sort out your feeling so you can make a decision based on logic rather than emotion. If you are happy not being a JW, going back might work for awhile but this problem will keep resurfacing until you sort it all out before you make a final decision.