Re: what would you do?
*What he is doing is breaching the spousal trust. Now its a tough and serious situation but you need to be calm and be in control of the situation then feel depressed about it.
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a. First of all, he is your husband, so you need to defend him not put him in the box to defend himself, you do that he'll keep on going back to his mother.
b. Don't fight / nag / cry or whine about it.
c. Talk to him like an adult that he is breaching your trust. Remember don't use negative words. Use positive words. Basically what you are doing is programming his brain into doing what you want. So its important that you use positive feelings and positive words. If you can, before you talk to him, write everything you want to say, sleep over it, go through it again, edit out things. Once ready, simply spit it out before dinner. Have dinner afterwards and give him a treat. A special one, something out of the ordinary treat. That special treat is to verify or to test him.
d. It very likely that he'll breach it again, since he has been use to it since childhood. That's where "behavior modification" comes in. Now humans respond well to love and affection much more quicker then they do to negativity or whining. So, if he ask for a treat, even after breaching the trust, he gets one but not the special one. Something ordinary. Every time he doesn't breach your trust, he gets something special. Every time he does, he get an ordinary treat. Point is, it makes you in control, and soon enough he will figure out how the whole treat system works. He will give up his behavior but not without a fight. What you did was gain control in the process, gave him a confidence boast, and built extra trust along the way.
P.S. In short, positive feelings expressed with positive words in a positive manner. What you need to figure out is the treat part. As much forward I may seem, men do generally respond well when they are intimate but don't discuss anything; during or after your intimate time.