You already have guessed why he still trying to have contact. You are his ego boost, he still wants a relationship, but not one that you would agree too!! He knows you won't, but he still gets to have a eto stroke every time he gets a reaction from you, thinking of how you are still missing him and how much you still love him, etc. Unfortuantely ego strokes are one-sided, the otherside of this equation only gets to live the hurtful feelings that are left behind!!
Keep doing what you have been=NC. Don't let him get his ego stroke from you! Remember your feelings are the only thing that matters now! Good luck