Who said “My own apartment, a car, and plenty of women? And still goddammit, I’m lonely”. How does it fit in with Marx’s point on capitalism?

Hap says this. His point is that he has achieved what could be called the dream for most people who work in a capitalist environment - possessions and plenty of interaction with someone of the opposite sex. However, Marx would make the point that possessions or hoping for the freedom that achieving the "American Dream" is supposed to provide is rather empty and does not provide the inner satisfaction that everyone should be entitled to.