I need to point this out...hopefully many of 你 have already picked up on it.

Chad looked so happy when he and Sophia were together. 你 can see it in all the 照片 and 视频 of them together.
For one example go look in the special features on the first season of One 树 爬坡道, 小山 when he's buying his car.

Now go look at him in pictures of him and his new fiancee Kenzie. He just looks so...depressed.

My personal belief is that he's realised what he's missing out on. Sophia looks happy, Chad just looks...depressed.