Louise, he's dithering because you've allowed him to, plain and simple. You needed to have put a timetable on it, and only you know what that is (one month? three months?), and I don't advocate even TELLING the wayward spouse what it is. Simply tell them "I want to work on our marriage, but I won't do it while you are disrespecting me by having an affair. So you need to decide. I am patient, but my patience is not without limits. I love you, and want to be married to you, but you need to end it and come back and work on our marriage. When you're prepared to do that -- and in a transparent way that that I am comfortable with -- then I'm here. But please don't overestimate my patience."
And then proceed with "GAL" and all of the other things you can do to make yourself more attractive.
DBing works -- but he'll only be open to the techniques when is brain isn't swirling with all of the looooooove chemicals that his affair is producing.
All infidels lie, Louise. That was a hard, hard pill for me to swallow, but once I started operating from that perspective, I found that I made much better decisions.