Diane Lane may have been ''Unfaithful'' onscreen, but in real life, she's ready to pledge her fidelity. Lane and actor Josh Brolin recently got engaged, E! reports. The couple, who began dating last year, are being tight-lipped about wedding plans, but did reveal that Brolin proposed over the Fourth of July weekend, according to E!. Lane, 40, was previously married to actor Christopher Lambert (''Highlander''), while Brolin was married to actress Alice Adair (''Beverly Hills Cop 2''). Brolin, who started his career with 1985's ''Goonies,'' is James Brolin's son (and Barbra Streisand's stepson). Lane, meanwhile, scored her first Oscar nomination last year for ''Unfaithful,'' in which she cheated on Richard Gere. But hopefully she'll treat Brolin better.