Help me find this book!

I read this book once on wattpad, probably around 5-7 years ago. But the author got it published and took it off Wattpad, and I can't remember the title. It was about a society where you had to find a mate or a match or something through your DNA or compatibility. You met with potential partners based on DNA but were allowed to deny them if they didn't feel right. Well this girl wasn't able to find her mate and because of this she was going to be incinerated. Here's where it gets blurry in my head. She was sent to this ship in either space or in earths atmosphere to be executed, where either modified humans or humanoid aliens lived that were really stoic and soldierly. The guy that comes to take her to the incinerator happens to be her mate. The book is then about the societal problems with them being together and their language barrier. People try to separate them. You find out in the end that the girl's father actually hid the truth about her DNA, which is that she was actually part of whatever her mate's race was, and their pairing was being observed to see if the two people were compatible. I really want to read this book again. Has anybody read this before?