Trusting,

He probably just got engaged to her to buy him some time..... would be my thought.

If he feels pressured at all, to me that's a big indicator he is not ready to get married.

If OW had any insight, this would be a clue that he's not willing to committ and she may want to move on if it's so damn important to her.

M=42 XH=44
M=18 T=21
D14 D11
Divorced 4/2012
XH marries OW 6/2014.