Re: reporting spouse to Dept of homeland security
Here’s a crazy idea…how about you don’t volunteer the fact that you did something illegal? 
Learn to play with words. If you’re ever asked how you met him…just say you met through family (ie. your parents have known his parents for decades). Technically…that’s not a lie. 
The word “cousin” doesn’t have to be mentioned at all. Going through this thread…it’s obvious that people here have no idea how USCIS works when it comes to marriage fraud.
PPride: If you haven’t already…you need to go back and carefully read what I wrote on page 1. That is the process you need to go through. I already mentioned what the tone of your letter should be. Allow me to add the following: stick to facts! USCIS doesn’t care about your feelings. The only thing they want to know is why you believe that he married you ONLY for papers and never had any intention to live his life as your husband. That’s it. Do NOT add any details that has nothing to do with him being dishonest about his intentions. Another words…things like him being your cousin doesn’t need to be mentioned there. I assume that right now, you’re a U.S. citizen. So the odds of anything bad happening to you are very close to 0. And I’m not sure what’s this “hassle” you keep referring to since all you need to do is write a da*n letter, get it notarized, and mail it in.
But you need to understand some things very clearly. USCIS is not going to go arrest him as soon as you send in your letter. They will not automatically revoke his permanent residency either. Here’s the ONLY thing that can happen: if and when he applies for citizenship OR the renewal of his permanent residency, USCIS will go through his entire file. That’s when they will come across your letter. Now depending on how convincing your letter is…USCIS can make it very difficult for him to get approved for citizenship. Worst case scenario is that USCIS will reject his application citing marriage fraud. At that time, he can go back to Pakistan or continue living in the U.S. illegally until USCIS deports him. But he’s not going to to go to jail UNLESS he commits an actual crime. USCIS is already overwhelmed and they’re not overly concerned with illegals who are not committing crimes related to drugs, violence etc. Most illegals get deported b/c they were caught committing some other crime (ex. DUI, domestic violence, drug posession, assault etc.) Of course, IF USCIS rejects his application b/c of “marriage fraud”, then that becomes part of his record. If he gets deported or leaves the U.S. voluntarily…then he can NEVER return. Having “marriage fraud” in your file carries a lifetime ban from the U.S.
Also on a side note: I read one of your past posts. You should not have gone for a no-fault divorce. If you wanted to increase the chances that he doesn’t get approved for citizenship…you should’ve filed for an annulment OR divorce citing fraud.