Hi, If those messages are somewhat threatening, I would consider filing a police report. If you do that, they may consider pursuing the culprit of the calls if they are threatening enough. For more info, read this http://www.privacyrights.org/fs/fs2a-cellcalls.htm
There is also a service that you can pay for that will apparently unblock any call. The person on the other won't know that you are seeing their number. I would definitely research this more before giving them any money though! http://www.harassingcalls.com/
Seems suspicious that they are happening when your H is not home! It sounds likes someone who knows what is going on so why wouldn't it be OW or someone she knows? I don't understand why your H can't see that.
But seriously, if they are too threatening, it doesn't cost anything to report them to the police. The OW in my sitch can be pretty nasty, I would not hesitate one second to file a report!
