Derivative of Swingers?
It's been a while since I've seen Swingers, but it seems very similar from what I recall... a sensitive guy upset over a breakup goes on a road trip with his good-looking, outgoing friend and meets someone? No?
shareBOOKLIST stated that the novel of SIDEWAYS by Rex Pickett was "A buddy novel in the cinematic vein of Swingers."
So there you go.