Pebbles,
Welcome to MB. I'm sorry you are experiencing things to bring you here, but this is a great place to be under those circumstances. I agree that your H is having an A. You need to do some more investigative work. It sounds as though this is someone he never intended leaving you over, so if you can find out who it is and expose his plans to her that may end the R. It also might bring things into the open because your H will likely be upset that you ruined his plans.
You also need to purchase His Needs/Her Needs by Dr. Harley. It will give you an idea of how to bring your H closer to you. It sounds as though he may in the early stages of things and there probably isn't much emotional connection to this other woman since he's still saying he loves you, etc.
You should really be worried when you get the "I love you but am not in love with you" speach that so many of us have received. That means he is probably ready to bolt. Hopefully you won't have to experience that.
Continue to check his voice mail. Check his emails. Put some spyware on your computer so you can track whatever goes on and if you can, do the same to his computer at work. As much as you thought you had irrefutable evidence, you need to have something where he tells her he loves her, can't wait to be with her again, or something along those lines.
Assuming you can never find any such material (although if he continues the A, you will find it), then do a really good plan A (which you can read about on this sight). Read the book I mentioned so you can start dropping major love units into your husband's love bank (as you read this site, you'll understand some of these concepts and terms much better), and talk to your H. When the time is right, make sure he thoroughly understands that if he had anything to tell you, good or bad, you're there for the long haul, you just want him to be able to tell you anything.
In the meantime, hold off on the family if you can. If your H is in the midst of an A, that isn't the best time to start a family. There are many people on this site who had to live through an A while being pregnant, and it's never good. Doable, yes, but recovering from an A is hard under the best of circumstances. Add the stress and anxiety of a pregnancy and you've just made it that more difficult.
Above all, make sure you don't do any lovebusters with your husband. Yet another subject you should read up on. They are the things that will make your husband withdraw from you. And so will a clingy, weepy attitude, which is another reason why getting pregnant now is probably not a good idea.
I hope for the best for you. If you want more responses, check out general questions. It's a much more heavily travelled forum and you're sure to get some good advise from some of the old timers on this board.