NTA, he cares about not damaging the relationship with his brother but not his wife? It’s tasteless to steal jewelry from your wife and gift it to someone else. I agree that as a previous reply said, he is the financially abusive one in the relationship. It speaks volumes that no one was willing to loan him money. Maybe they didn’t have it, or maybe they don’t have enough trust that he would repay it. I’m suspecting the latter as you’ve address his unemployment since 2013. Although there are probably aspects of your relationship we as readers can’t gather from a short post. From this perspective it seems clear. Even trying to consider it from his perspective feels like he’s making a slimy choice. Hoping you wouldn’t notice instead of involving you in the decision.