In most instances (I did not say ALL fellow readers), a marriage's success or failure relies on both participants. So, please don't feel you should bear the burden of this as your responsibility alone. Sending prayers your way.
I agree with this....I also don't know your entire situation, but for dh to end your marriage over your gd? Maybe theres other things going through his head than he has admitted, and this is why he needs to agree to counselling..It's not fair to you and the boys otherwise. Please don't take complete ownership of the marriage breakdown..As JCG said, it takes two to make a marriage work..
Sending hugs to you, and hoping everything turns out ok for you all..Stay strong..