I thought by him saying "Make up your fucking mind, while you do I'm gonna be fucking someone else" was the most straightforward shit he has said to Sloan all season.
He knew that Sloan wasn't planning to hook up with him at the bar, she said it was friendly, but who knows what could have developed after a few honest drinks. This whole time Sloan hasn't been sure about E because E's been unsure of himself; women sort of like confidence. Why would he think Sloan would want to get back with him after he continues to act like a kid to her and decided to go with Ashley, who Sloan knows is below her? He's sensitive and not exactly smooth on top of that.