Fall into her trap and kill her.

Getting inside her car, as they haven't walked too far before Wilson confessed, Diana drives off, with tears streaming down her face. 

She wasn't crying because she was made a fool of. She was crying because history nearly repeated itself. 

Ashley is the one that's just like Shane in this situation and she will make sure to deal with her without mercy. 

The feeling of, 'what if Wilson didn't confess' scares her. 

She knew Ethan wouldn't allow his kids to get hurt, but not when the person that wants to hurt them is Ashley. She's an insider and Ethan might realize the blow when it's already too late. 

She's nearly going insane. Even though it will be prevented, it still scares her. 

When she finally got home, she had calm and wasn't all riled up like before, as there's nothing a long tiring drive can't control. 

She decided not to say anything to Ethan. 

The reason Wilson made the mistake still stung onto her heart like a needle.