This week, “Addicted to Sex” – Bryan Ferry once sang: Jump up bubble up/What’s in store?/Love is the drug and I need to score. He’s not the only one with a sex addiction. Staff writer Lauren Gard shines a light on a dark corner of modern interpersonal relations, where guys (and an increasing number of women) visit porn Web sites, massage parlors, Match.com, X-rated video stores, and, eventually, Sex Addicts Anonymous and other self-help groups in their efforts to catch that buzz and then, usually after they’ve been nabbed with their pants down, to repent their sins. Some experts blame the Internet. Others, endorphins. A lonely few blame Barney. Me, I blame Russ Meyer.