Charondog...sorry to hear about your family circumstances. The following recent article may be the reason why your parents responded the way they did:
April 2018 WT study for this week page 24 par 17 entitled "Encourage One Another All the More So" reinforces their shunning policy:
"Henri, a young brother, was greatly distressed when his close relatives, including his father, who had been a respected elder, left the truth. Henri was encouraged by a circuit overseer who took him to a cafe for a cup of coffee and allowed him to open his heart. Henri realized that the only way to help his family come back to the truth was for him to persevere faithfully. He found great comfort in reading...blah...blah...blah....."
Your parents' faithful perseverance to this cult's repeated pipe-dream drumbeat about the high probability of your returning to the 'Truth' if they continue to give you the cold shoulder isn't helping your cause any!