02/06/2007 AT 09:15 AM EST
San Francisco Mayor Gavin Newsom said in a statement Monday that he plans to seek counseling for alcohol use. His decision comes less than a week after he publicly apologized for an affair with the wife of his campaign manager.
"Upon reflection with friends and family this weekend, I have come to the conclusion that I will be a better person without alcohol in my life," Newsom, 39, said in the statement.
Newsom – who said he has already stopped drinking, but wants professional help to remain sober – added that his "problems with alcohol are not an excuse for my personal lapses in judgment."
"I take full responsibility for my personal mistakes," he said.
Last week, the divorced mayor publicly apologized for his affair with Ruby Rippey-Tourk, 34, his former appointments secretary and the wife of his campaign manager. Her husband, Alex Tourk, 39, resigned Wednesday after confronting Newsom about the relationship, the Associated Press reports.
Newsom – who gained national fame for championing same-sex marriage – said he will get treatment from Mimi Silbert, the founder and director of the Delancey Street Foundation in San Francisco, and that his duties as mayor will not be affected.
According to the AP, Newsom founded a wine store, a string of restaurants and the Plump Jack Winery in Napa County before taking office in 2004.
Last year, Newsom, who is divorced from Fox News anchor Kimberly Guilfoyle, dated CSI: Miami's Sofia Milos, who told PEOPLE: "Gavin is not just a handsome, charming mayor; he's also passionate."
Newsom is running for a second term in November.