Confusedinlimbo - I don't think you are wrong in putting up this boundary. You have the right to step back until your husband has cut all contact with the AP, that really isn't much to ask.
If he tires of you having this boundary up then I would question how much he is genuinely committed to the marriage. If he really wanted to fix things and to work it out with you, then it shouldn't tire him at all. He should recognise you have to do it - and it is his choice to stay in contact with the AP.
He says he needs to "get rid of the connection that's still there". I think there is only one way - NO CONTACT!! While there is contact, there will always be a connection. I might be wrong, but if he is trying to wean himself off the AP gradually, so that it's less painful, I am not sure that will ever work. He will have to go through the pain. I think this is what my husband tried to avoid. He couldn't stand the pain of no contact and he also couldn't stand to hurt the AP in the same way. So minimal contact was kept, and the result was the connection never went, and the affair just went on, and on and on.
If he really, genuinely wants to get rid of the connection then he has to realise no contact is the only way, and the connection will gradually diminish. But I do believe it can take a long time, especially when strong feelings of love are involved. He will have to tough it out basically! But how do you get him to do that or come to that realisation - I don't have the answer to that. If I did then I might have been able to help my husband let his AP go. He couldn't do it, so I let him go instead.
How are you doing? I haven't seen you on here in a bit and I've wondered.