The best thing you can do is make undoutly clear how you feel about it. He is young and at his first job, he needs to learn the rules. And you teach him that scholar behaviour (divide and conquer) work. It might help to tell him about the old topic. This topic is just a selfish, I need a shoulder to cry on topic.
Confront him how you feel, and give him advice 'If I were you I would do....', however don't make it look like you are just putting stuff back. Provide help and support.
In some ways you are his mentor, so tread him like a serious person.
Remember in most sociaties 'No' is a valid answer, if he asks for you to put the wire straight just say 'No, remember what we discusses?'
If this all doesn't work, and don't be easy on him like you were on his wife, then you should go to your supervisor and ask how you should deal with him in general, not this specific project that might be due in 3 days.
Good luck,
Ton