performance I remember your previous thread. I'm so sorry you're still in pretty much the same place (with a lot more contact).
I honestly think that if there still hasn't been any movement from him or any indication of what made him change his mind (because he has) then you must now begin to make your break from him.
I'm really struggling to understand why he is continuing to spend so much time with you when he has clearly stated, and continues to state, that he's no longer in love with you. That is cruel, IMO, depression (if that's the root cause of his change of heart) really doesn't rob anybody of their morals, intelligence, respect or basic human kindness; he must see how confused, desperate and upset you are.
If he really believes there is no way back as a couple, he should be respecting your need to process the end of your r.ship, not meeting with or talking to you at every opportunity.
You know you're doing yourself no favours by tying yourself up in knots and expending all of your time and energy trying to make sense of his behaviour, and it certainly isn't good for your DC. Fair enough they're visiting their gran but unless you are in a better place and feel stronger, in yourself, they'll pick up that things aren't great as soon as they're home.
FWIW - I now believe that some men (and women) are able to just stop feeling, on a whim (or at the very least are able to block their true feelings, even from themselves).
I think if there's something, anything that is frustrating them within a r.ship that they don't foresee will improve, and if it annoys them enough, they can just think 'enough' and it really can be that simple.
Please, for your own sake, stop all bloody contact. If there's a way back, for him, he must find it himself.
Good luck