Your interest in drunken evenings strongly suggests to me that you would be much happier in San Francisco. Why not look for a summer sublet South of Market (e.g., a Golden Gate University student gone for the summer)? You could walk/bike to Caltrain, then 50 minutes to Mountain View (bikes allowed on board). Castro Street starts right at the Caltrain station.

Life is way too short to be young, single and looking for nightlife in the South Bay.