Thank you so much for all of your responses! I figure that most of you are talking from experience.
To update, I am still feeling very lost and confused! Part of me still wants to believe that he will never do it again, but then part of me KNOWS that he will. I realise now, that he was crying after he did it because that was part of his minipulative side!
I've been trying to wrack my brains and you know what?.....In all the things he said the day after, I don't think I got an apology! All of it was about him. How HE would cope without me and how crap HIS future would be. I swear the morning after it happened I was the strongest person I've ever been. What I was saying to him 'youve made your bed, you now have to lye in it' 'you need to get help' 'god help the next girl that comes into contact with you, if you don't get help' and then it all went to crap and he cried and snaked his way back in. And I felt guilty and sad for him. I realise now, that is EXACTLY what he KNEW I would do. He knew how to work me and make me stay.
I realise this now as I have started seeing a therapist and also from your kind words in this thread.
Thanks for the support!
This marriage is absolutely dead and there's no going back..