OP I hope you don't mind me joining so late.
IIRC this is the first thread I have ever read on Relationships.
Please, please, please listen to all the other postsers on here.
I found out that my fiercely loyal, faithful husband had joined a dating agency in November. By December I'd also discovered that he was having an affair with a woman from work. How tediously pedestrian 
It's because I was emotionally distant. Er. Because he thought we'd made a mistake marrying in the first place. Er. Because I'd never made him feel special enough/like he was loved.
He wanted to try again, he thinks he still loves the OW, but he still loves me. I can't say anything because I have "no right to tarnish the most amazing few weeks of his life"...
I've read your posts thinking "yep, heard that"... "yes, heard that"... "oh my god, yep, heard that too".
He's begged me to let him hold me when I was upset, and become nasty when I said he isn't the person who gets to do that any more.
He's now told me he needs time to decide whether it's me he really wants or the OW
because he still loves me, but he doesn't know if I'll ever be able to trust him again. (See, still my fault!) Oh and yeah, right, of course I'm going to wait around to see if he wants me or not. Idiot.
It's all my fault. He'd never have done any of it if I'd loved him more or been a better wife. Bollocks. He did it because he's a man, just like the others, who thinks with his dick.
You have to start listening to his crap for what it really is and rise above it. And whilst he thinks you are there willing to take him back if that's what he decides, he will mess you around. You are better off without him.
A lot of people on here said to me that I'd be ok and it's hard, but on the whole I am.
You deserve better than this.
He is following the script. I had never heard of the script. But it exists.
Your husband is a twat, like many before him and many yet to be discovered.
Makes me wonder if there are any genuinely faithful men out there!