that being the case hippyhoppy maybe a suggestion made by another here , that your children call him to say hi wouldnt be such a bad idea.
if he is busy it will be a wake up call , if there is another reason for his absence then it will be made clear.
as he " if i read correctly " has another woman in his life , your ringing him would mearly make it look like you yourself are still interested which could cause issue's that are currently may not be there.
once the call has been made , he should be the one to contact . " unless your child / children want to try again. but in all cases it should be his and their attempt to continue contact " for reasons already stated.
hope this helps