for whatever his reasons, and it doesnt mean to say he is a bad guy, his intentions may well have been genuine, but maybe with his commitment to his own kids, and the pending commitment to you and your children, the needed anulment and all that it involves you becomming together, is such a lot to take on, it looks as though he has realised this, and now so should you,
he has come to realise his commitment is firstly to his own children and thats enough for most to cope with,
dont waste away your life waiting, your still young and you will and do have time to find someone who can give a life shared with you as a family