just tell him/her tat when he married, he oso nv invite u . so u
r merely jus doing wat he was doing unto u. fair n square
wat...
either tat, jus argue tat u sent the invitation. he nv receive is
his problem, postman problem, not ur fault. truth is, u did not
sent in the 1st place. 
tell him , dont worry. u nv invite him during ur 1st marriage.
assure him u will invite him 4 ur second wedding. this time, dont
forget to invite him.
or, u tell him sorry becos u nv him to ur wedding. assure him tat u
invite him to ur divorce ceremony. throw big parties at hyatt n
Carlton hotel to celebrate the occasion.
