Most Helpful Guy
For Karma to work, you must forgive and let nature run its course.
Him talking behind your back and he being in an affair while married at the same time, he was dating an employee makes for a busy boy.
If his talking about you is affecting your work with your new employer, you can file a complaint about him with the regulating employment agency and he will go on point. If he has dated another employee, then the wind has just been knocked out of his sails and he will be packing his panties to look for another job.