Search Results: forgive me god

Let's put this in a scenario, (because it's something I've actually witnessed)

What would you do in an instance where you are dating someone who has been divorced in the past.

You and that significant other have a child.

You raise that child up past the age of 13.

Your significant other then comes to you and admits to you that this child you've been raising has not actually been yours, but someone's that they had an affair with without your knowledge.

But because they found religion/God and came to you and told you, they feel like you should forgive them and continue to raise the child as you had been for the past 13 years.

What would you do? Choose one of the options and/or explain your reasoning.