What moved it along for us is when I told Daniela that she could act on her desires/fantasies however she wanted, and that I would do nothing, other than what she asked of me. And she did: first called an ex-boyfriend, second met him for dinner, third the three of us had dinner (where I made it clear that I was ok with them getting together), finally they started fucking. Then she did the same with another ex. It was fantastic all around, including me - sex afterwards was unbelievable. Daniela then had me join for MFMs, a whole other level.
I would have been fine staying with that, but we now play within a closed group of married couples, so it's all worked out fine with me letting my wife start by doing what she was comfortable with.