As the child of divorced parents, I see a lot of crap in the press about how getting divorced is always damaging for children.
OK, it was not ideal - I have had some unhappy times. No, I am not a perfect person but then I don't expect I would have been anyway. I have had some periods of (not very serious) depression and panic attacks, like 25% of the population.
But I am fine. I did well in education, I have a good job, I'm in a good relationship, like pretty much all my friends with divorced parents.
My stepmother gets on my nerves often - such is life. I like my stepfather a lot. I have a good relationship with both my parents.
Would it have been worth my parents putting up with a marriage which I can now see was patently not viable for my life to have been about 10% more pleasant? Not really. Bit of a waste of time, if you ask me.
Some friends of my parents impliedly criticised my parents for getting a divorce and have stuck out their marriage 'for the children' and now seem slightly disappointed that I am not a car crash of a person, but am in fact doing just as well as their children. And my parents are happy with their new spouses.
I think the biggest risk is that your DH will eventually realise that he is living with a faker. He would have to be pretty emotionally dense not to realise. He may feel unloved/rejected but not know why because on the surface everything is normal. Perfect conditions for him to go off with someone else.