Richie made the revelation during testimony at London's High Court on Tuesday (10Mar15) during a hearing to work out a compensation package for the actor and two others, Shobna Gulati and Lucy Benjamin, after the trio won a legal battle with Britain's Trinity Mirror group over voicemail message snooping.
While on the stand, Richie revealed he and Wallace, who play husband and wife duo Alfie and Kat Moon in hit soap EastEnders, fell out because of the phone hacking.
He told the court, "After a while, me and Jessie didn't speak for five years because she didn't trust me and I didn't trust her because we both thought we were selling each other down the river with stories, which it turned out of course wasn't true... (Everyone was) pretty paranoid and suspicious of each other which was a horrible feeling."
Richie's testimony followed that of fellow EastEnders star Steve MCFadden, who told the court that stories which originated from tapped voicemail messages destroyed his romantic relationship with former co-star Benjamin, who played his onscreen lover in the show.
The probe into Trinity Mirror, which publishes newspapers including the Daily Mirror, comes after a high-profile inquiry into the activities of journalists at Rupert Murdoch's News UK, the company behind now-defunct tabloid the News of the World.
The publication was closed in disgrace in 2011 amid claims a private investigator hacked the voicemail accounts of thousands of celebrities on behalf of the newspaper.