Chad Ochocinco & Evelyn Lozada -- Wedding Plans on Hold, Cheating Suspected

Chad Ochocinco's famous fiancee has slammed the brakes on the couple's wedding plans, TMZ has learned ... all because she suspects the NFL star has been messing around behind her back.

Sources tell us ... "Basketball Wives" star Evelyn Lozada recently confronted Ocho after she became suspicious about his behavior ... and she isn't convinced he's been faithful.

The two are set to be married in the summer -- and while Evelyn hasn't "officially" cancelled the wedding yet, we're thinkin' the priest should start making other plans.

Plus, Chad and Evelyn were supposed to begin shooting their new reality show in just three weeks ... we're told that plan is also up in the air.