In all honesty, Fiz should have seen it coming. Should have known that once Jemma got back she wasn't going to instantly fall in love with him. But that wasn't what hurt the most, oh no because Jemma was in love with someone else now and she was willing to go back to her hell to save him.
So Fiz closes himself off to her, became distant because that was the only way to stop himself from blurting out all the things he's wanted to say for her for a long time. But those words are there, boiling under the surface, screaming to be let out. Fiz won't let them though, and he pushes them down.
/
Fiz couldn't even hate Will Daniels, the man Jemma fell in love with. In fact, Fiz was grateful, he saved Jemma and kept her alive, and that was more than Fiz had done.
And Jemma, oh wonderful sweet Jemma. He'd thought she'd be his, thought she'd always be waiting for him- he was ignorant to have ever thought that. He couldn't bring himself blame Jemma, she wasn't obliged to love him!
But it still hurt, though, when she told him the truth. He tried to smile at her- but to him it was more of a grimace- to hide the pain in his eyes, and he must have done better than he thought because she didn't notice. Didn't notice when he promised her to help find Will that his heart broke even more, that it shattered inside his chest and felt like a million bullets hitting him with each torturous beat. Didn't notice that despite all that, somehow, he still loved her. Because he would do anything for her, even if it tore him apart.
/
She was happy.
He told himself, late at night while he was sitting in the lab, staring at complicated equations scrolling across the screen, wondering, what if? What if Jemma loved him instead? Fiz shook his head, he made a promise, and he intended to keep it.
That's all that matters.
Liar.