Dean tilted his head where it was rested, curious about the conversation but intentionally not asking, because he didn't want the details. He didn't want to know what it was that had been said, it'd just make more of a problem. In a way, Jo was to him as Jess was to Sam and his mom was to his dad. She was a girl he'd gotten so close to he could have had something and instead of embracing that he'd opted for the safe route. She was his sister-figure instead, she was the naive hunter who followed him around with the crush, and it wasn't until Jo was bleeding to death that he had opened his eyes to the way he did feel about her.
Of course, with the time, and that trial with Osiris, he'd been able to move on gradually until Mandalus. Jo wasn't Lisa, Lisa was the woman he had loved, Jo was the girl he'd pushed away because wrong place wrong time was their motto.
"I guess? I don't know. It's just a whole bunch of emotional crap that I just don't wanna deal with." He reached to run his hand through his hair, resting his elbow on the edge in front of the closed window. He'd never be over Jo, and he felt like Castiel was his but he was stupid to think anyone was his. Sam was the nearest person to him he could entirely claim and he still had to share him with the world. "I had a shoutin' match with Jo about it, told her how it looked like she couldn't have me so she hooked up with my best friend, she said that's not how it is. She'll probably tell Cas, if she hasn't already." Then things would turn to shit really quickly.