You can't win with family. Several good points here in this thread. Although technically you are right and you never got your share of the $3k, I would just let it go. Now you have to appease the wife because you are the supposed 'bad guy'.
My wife is the black sheep in her family. We exercise, are thin, have money and are totally different from the rest of her family who struggle. They resent us, backstab us but this is not unusual. Siblings, bil's, sil's can end up in the 4 corners of the ring.
Time will heal this and after a while it will be a bump in the road. Take the wife out for a nice meal. I understand where you are coming from. I vote with my feet and hang out with people that make me happy. My wife makes me happiest. But she still gives me supreme heck coz of the way I handle some of her family. Just don't expect
people to behave the way you would.
Cheers, Guy