The only thing I can think of is:

showing him that you are moving on with confidence- if he feels afraid to lose you he might want to give your R another chance

seriously-bring a fella around, have the kids report to him about the nice man that Mommy met.

How old are your kids?

me,34
exH,34
S,16 months
S:3/31/09-left for OW
started DBing 10/09
d final: sometime 10/10
current:
http://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2022856&page=1
met in 2004