Sydney, Your initial post sounded exactly like me!! I have been where you are, to a tee!! But, I didn't find this site in time and we are now D. He also had an OW until about a week ago. He has admitted that we D'd too soon. He has said a million things, in and out of the tunnel. I am pretty much dark on him, but it is easier cause I live 700 miles from him. It took me a long time to get there, even from so far away. I, all the time, refer to my XH as an alien! He was taken 3 years ago, almost overnight as you have said. He was an incredible husband and father up until that point, we had issues, but nothing I thought would make this happen. We talked many times a day while he was at work or wherever and he always called me "love of my life" In October of 2006 that ended almost over-night!!
I have struggled with the whole issue of knowing he is mentally ill and still leaving him. But, I know I did everything in my power (at the time, with the information I had) to save our marriage. I also know that I couldn't watch him be with another woman and survive. My kids needed to have a mom who didn't cry all the time. I am stronger now, only divorced 8 mo., but it is getting easier. My 10 yr old said when she heard XH and OW broke up "now you and daddy can get back together". I doubt that will happen, the lies, deception, pain, loss, etc is just too much now. But, I never say never. He won't even be my friend at this point, he blames me for every single thing that has happened, I am sure even that OW dumped him is my fault, lol.
Hang in there, I wish I had!! I know your pain! It is unbelievable at times, feels like you live in a twilight zone! Just leave him alone, let him live in the bed he made.
Me-40 XH-44 T-21 M-18 Div-19 mo. D-18,S-15,D-11 Bomb-7/07 EA,PA Mvd out-9/07-to give me space mvd back-12/07 mvd out-7/08 back with OW since 2/08 OW broke it off-1/10 in and out of tunnel and our life since!!