How does henchard intent to recognised susan as his wife without revealing their guilty secret to elizabeth jane

From the text;

"No, no, Susan; you are not to go--you mistake me!" he said with kindly severity. "I have thought of this plan: that you and Elizabeth take a cottage in the town as the widow Mrs. Newson and her daughter; that I meet you, court you, and marry you. Elizabeth-Jane coming to my house as my step-daughter. The thing is so natural and easy that it is half done in thinking o't. This would leave my shady, head- strong, disgraceful life as a young man absolutely unopened; the secret would be yours and mine only; and I should have the pleasure of seeing my own only child under my roof, as well as my wife."

Chapter 11