I saw a quote recently, that applies here:
“If a guy is staring at “unfiltered internet access” and eating cheeseburgers, then he is normal. If he is eating “unfiltered internet access” and staring at cheeseburgers, then he needs help.”
That being said, it certainly is an issue in a Frum relationship. Certainly don’t get the children involved (a HUGE mistake). The couple should certainly go to a Rov who is an expert in these issues. However, greater people than her husband have been Nichshal. Didn’t we hear about the “Rosh Yeshiva” in the pre-Asifa ads that was Nichshal? It doesn’t make him not a Rosh Yeshiva, it makes him a Rosh Yeshiva with a Yezter Hara.
So basically, I agree with Choppy & Toi, but was somewhat more wordy.