I think the advice above was pretty harsh. People come here for advice, and there is a whole forum for those already divorced that don't even care if they reconcile with their ex. I see where the poster was coming from, but unless you've been in that situation, it's very hard to understand the concept of moving on.
That being said, I think you probably did jump into this relationship too soon. Don't you? But what about your ex-W? Have you really taken a good long look at what she has to offer? You are out of the marriage. It is the time to look and say, "what does she bring to the table? Is this two complete people that bring out the best in each other? Or do I just miss having the family?" It's fair to do that. Can you answer those questions fairly? In my case, I think a big part of wanting to reconcile the first time was I missed my kids so much, rather than I really wanted my wife. Now, many years later, I can't even see what we ever had, much less what we could have.
Okay, last advice. You need to soul-search here. You may be a good guy, but what you have going on at the moment is not. It is not fair to this new woman to be this way. It's dishonest (unless you told her that you're still hung up on your ex-W). You owe it to yourself and to this new woman to actually make a conscience decision one way or the other. It's not fair to use this woman as your crutch to be discarded if your wife shows interest. Are you going to be with the current gf or not? Decide you will and put the work into it, forgetting about these "what could have beens" with your ex-W, or break it off with your gf and pursue something with your ex-W. This middle ground doesn't cut it.
In the end, it's not the years in your life that count. It's the life in your years. Abraham Lincoln
It is hard to fail, but it is worse never to have tried to succeed. Theodore Roosevelt
