He explains he has decided to send the letter out to all of their family to express his side of the story and hopefully put an end to losing more family members because of his parents' stance.
He describes the day his parents told him why they would not be attending his wedding:
On the way to lunch with his parents, he had begun to share his excitement about how his partner's relatives were coming from all over the country to attend the celebration and were excited to meet his family.
But rather than sharing in their son's joy, Bradley says his parents chose the moment to inform their son that they would not be attending his special day.
He writes that they began reciting passages from the Bible and claimed they couldn't attend for fear an angel would appear to them to say: "Stop praying for Patrick! He's already in hell!"
It was at this point that Patrick gave them an ultimatum: If they didn't make it to his wedding, he'd stop visiting them.
His mother responded: "We know that! I talked to your dad last night and we already accept it! We said that we give you back to God!"
Bradley's letter recalls his reaction: "As I sat in shock - shock that you would rather never see me again than attend my wedding - you simply moved on to your next subject: 'Well, I guess you don't want to go to lunch anymore'," .
"As I opened the car door to walk back to the train station, you offered, 'Let me drive you back to the train. Let it be the one last thing that I do for you'."
The rejection has stayed with Bradley who, two years on, has decided to extend an olive branch.
"I will forgive you both for what you have done, if you, in front of the entire family (from youngest to eldest) admit that what you both did was wrong; admit that you both should have been at the wedding," he wrote. He said he thought they should feel shame for how their decision has affected their grandchildren, "whose only conclusion was perhaps 'Patrick must be bad'".
"I want everyone to know everything," he concluded. "And maybe tonight, I'll finally be able to sleep the whole night through."
- nzherald.co.nz