Geez cut him some slack, its clear he'd knownhis ex since school shown in the flash back, obviously hes pissed she left him for a rich man, but he needs some time to get over it. I personally think the current relationship has gone too fast. It shouldnt be until they been through some experiences and having each other back, should they develop the more romantic relationship. Its fine with them just teasing each other atm to break the ice. The works fucked afterall, dont want to be too hasty