I too am confused by your post...
I have a rider on my jewelry. So I do not understand why the insurance company will not replace it. Something of that value, i would DEFINITELY make sure it was covered.
You have sooo much going on right now - is your daughter healthy yet? I would not make life altering decisions when there is so much going on.
My engagement ring was stolen in 2004. Today is our 14th wedding anniversary.
I would strongly suggest marriage counseling before you throw in the towel on your marriage. it's not easy. And you have a lot going on. For me? I don't need a wedding band or an engagement ring to be married. While I understand the importance to you of having a ring and I think it sounds like you are sooo angry at your husband for more than this that you are making this portion out to be more...yes. It IS a high value ring - but really- it's a RING.
Men are wired differently. My husband wasn't upset over the loss of my engagement ring - he was mad - but he was like - okay - find a new one and press on. He's probably focused on you allowing men posing as repairmen into your home...and more concerned about you and your daughter being harmed than whether or not you lost a material item. That's a man's brain...protecting family! material things can be replaced. he's trying with a wedding band - you both are focused on different things...you need to learn to communicate with each other so that you can get on the same page...
Please go to counseling so that you can salvage your marriage.