Wife cheated, wants to babysit the other parents kid. Am I crazy not being on with this?

My wife has been having an affair since December. The other person is her best friend, a single foster mom who lives a few hours away. She confessed the affair to me yesterday. We were scheduled to provide respite for the child of the woman she had an affair with, starting tomorrow and lasting a week.After the affair I decides I am not comfortable with this. She thinks I am being rediculous, and driven by anger. She is going to go get the kid today, against my wishes.I am in the wrong not wanting us to babysit the child of the person my wife had an affair with? My wife is still not decided between staying with me to heal our marriage, or leaving me for the other person.Picked the parenting subreddit cause I do not know where else to ask. We have 3 kids, all came to us via foster care. The other person is another foster mom. For the past 3 months my wife has been taking the kids there often so all the kids could play, but turns out she has been having an affair as this has been going on. via /r/Parenting http://ift.tt/2HG9ydH