Your hubby didn't stick to his marriage vows, so I would not trust him to stick to an agreement for an amicable divorce... Just saying.
He's a real low life idiot, you deserve so much better.
Stop playing nice and make sure your kiddos are protected financially by getting a lawyer, you may not want one, but they need one.
This whole house business?
He may be realizing he can't entertain his new flooze and maintain his responsibilities long term, so he's already looking into cutting costs.
Don't let him off the hook so easy hun