It's great to hear that your BF is still thinking about you so much. But it's good to think about what it looks like when they come back (if that should happen). Because, remember, they are still caught up in wanting BOTH of you to meet your needs at that point.
Right now he's got Helen, so you're the one that looks attractive. But if he breaks things off with her so he can have you ... what almost always happens is, he starts to think more and more about the OW. And next thing you know, he's stepping out to make phonecalls, he's got the alien look in his eyes again, and the cycle begins again. Are you prepared for the yo-yoing that comes with the WAS's first attempt to return? And many of them bounce back many times before they settle down....
At this point, most WA's are like drug addicts. They still long for the "clean" life they used to lead (you) and are ashamed of the cocaine addiction (OW). Sometimes they think they can leave the addiction behind and go back to their previous lives ... but unless they've actually dealt with the issues that led them to cocaine in the first place, they won't make it. That isn't to say it can't happen, just that the spouse who's been left has absolutely no control over the other person's choices.
The good thing is, once they've faced the fear of death/aging/self-esteem issues that got them there in the first place, you won't need to describe them as "weak" any longer. They are strengthened by facing their fears, by fighting their addictions, and by having finally chosen the lifestyle (and partner) that they want.
What I'm trying to say is, I think your R has a good chance of being strengthened by all this. But not yet. You don't want to take him back until he is no longer confused at all, but has really "grown up."
In the meantime, I heartily second Transformer's suggestion that you read PM. It is the best book about becoming a truly mature and fulfilled person--by expecting only the best from yourself--that I have ever encountered.
