From what I understand, sociopaths/ psychopaths can feel contentment and roller coaster thrills with the right stimulus (like an actual roller coaster or a car crash) but even that response, which some feelerz experience in its most intense form, as fear, is felt to a lesser degree by 'pathy people. They describe it as smthg closer to a scary movie feeling. Mildly startled, but in a fun, nearly happy sort of way.
^ That sounds close enough to happiness for my definition. It's not joy, exuberance or ecstasy, and it's far from love. But I'd say a good percentage of the paths I've met can feel "happy" (ish.)
Love =/= entertainment. It's an intense physiological sensation that's very close to an opiate high. There's no mistaking it. If you're not sure whether you've felt it or not, you haven't felt it.