I want to trust him again

[Jen_Jam]

Oh UL, honey, you have not undone ANYTHING!!!!
Sometimes R talks are good for clearing the air, I think in piecing it's OK to have them just not loads of them, not very long ones.
It's SO GOOD that H has dropped the OW and wants to try. You have blown NOTHING!!!!
My H and I had a similar convo a while back, (there was no OW in our sitch but that's beside the point) he said he didn't want us to split up but he had no idea how we were going to stay together either.
What worked for me was giving up on any kind of romantic R with my H for the time being and deciding we would become great friends and hope that love grew from that. I lokoed at the problems I had caused in our R and eliminated them, I looked very much at myself and worked out why I was causing the problems which helped too - I knew that even if my M failed I had to get rid of the bad bits of me, or I was never going to have a happy R again, with my H or anyone! We also did some Relate sessions which helped H open up to me a bit more, he liked the "controlled environment" where I couldn't start crying or shouting. At the end of the sessions (we did abotu 6) the C said our R was healthy and in good shape, but we just needed time to reconnect. She wasn't kidding! We needed MONTHS of reconnecting!!!! But we got there in the end.
I haven't read your whole sitch so I don't know what your particular problems were, but my advice now is that you have a H who doesn't want to walk away so BIG DEEP BREATH and remember to go slow and take things easy. You will likely be at this for a fair few more months, so be patient but if you keep up the DB'ing (and it seems you're good at that so far - well one) you are giving your M its best chance.
Remember too you have blown nothing - it's just a slip up. Say you were painting a room and you got somethign wrong - you wouldn't give up on decorating the room, you would put right the mistake and carry on. Also like dieting - if you have one day where you blow it you don't suddenly get fat again, you just say "oh well" and start the diet again.