It'd be a pretty big shock to find out that you are moving within weeks, probably had given notice on the apartment, you are pregnant, now there is no school, ho housimng, no job, no scholarship, or grant. She's thinking, "I've got to confront him and find out what is going on." Now she finds out that his previous college graduation was faked. She's been married to this jerk for 5 years and now she wants to kmnow what else he's been lying about...
Do you think those extra hours would have changed anything? I'd guess she took those hours to go think somewhere. Being at work and upset, she probably wouldn't have been able to think and would have been asked questions. The article states that she was a private person that didn't talk about personal things.
I surmise she wanted to be alone to consider her options. I think she may have confronted him at home. If she had driven, she could have done her thinking after work, but I gather from previous articles that he drove her to work. Why he felt he needed the car more than her is beyond me. Unless it was another means of controlling her. They may have agrued and he may have said he'd go ahead of her and find a place, look for a job and or enroll in some college to pick up where he left off. He may have reassured her. Temporarily.
Notice in the snips from the other thread that she told her friend that he was going and she would follow later.
Its possible that he didn't trust her to not speak about the lies to her and his parents.... or that they got into a renewed arguement and it got out of hand.