Andre is taking libel action against Price over claims she made that he was having an affair with his manager Claire Powell and that he had chosen not to spend time with his 8-year-old stepson Harvey.
"Peter has never done anything wrong, never been unfaithful and is determined to put the record straight once and for all," a source told the Daily Star.
The singer is apparently worried about what his children will think of his decision to take Price to court.
"Peter is really upset that it has come to this and the strain is enormous. He’s trying to keep things as normal as possible for the kids. He's dreading the effect this case will have on the children," the source added.
"It's so sad that it's come to this but Peter wants to clear his name once and for all."
Andre and Price will both testify when they appear at London's High Court on Thursday.
> Price 'advised to hire extra security'