LAWRENCE — Jose L. ­Santiago — an ally of Mayor William Lantigua of Lawrence and also a former state representative and former Methuen police officer — warned an ex-girlfriend, a prosecutor said yesterday, that if she broke off their relationship “you’re not going to be with anyone.’’

Santiago, 53, was charged Monday in Lawrence District Court with violating a restraining order the woman took out against him. He was arrested early Saturday outside an Essex Street club after a friend of his former girlfriend spotted Santiago in the parking lot, the prosecutor said.