to think soon to be ex FIL is wrong to open my mail?

[rotool]

OK so my mail sometimes ends up at my inlaws ( soon to be ex ) as they live next door and my FIL opens it. It has his address on it but my name due to having had to live there for 7 weeks three years ago .
I recieved a letter from his Solicitor today advising me that FIL had asked him to write to the companies involved informing them that I do not live there.
For him to know the names and addresses of the companies he must have opend my mail. I'm mad that he has opend my mail and mad that he couldn't have mentioned it to me via mail, or his son ( my soon to be ex ).
Am I being unreasonable to ask my Solicitor to write to his complaining that he should not have opend my mail?

So the FIL could potentially be committing an offence if he opens the OP's mail with a view to intercepting legal/solicitors correspondence? Or hoping to gain confidential information to use against her?

I agree with solicitors letter. But OP would need to prove that she had contacted all those who were still sending stuff to the wrong address to make sure their database details were up to date and the old ones deleted. Easier said than done. When my dad died we cancelled his subscription to National Geographic magazine and also the direct debit. In spite of receiving a copy of the death certificate and replying by letter as well, they still kept on sending the magazines. Trying to get them to stop was impossible. I bet the OP's old address is still on the databases as well as her new one, same name, different door number, same road name.

Mail redirection service by the Post Office doesn't always work efficiently either.

I get plenty of mail from companies where it says on the envelope who it's from, so he wouldn't necessarily need to have opened anything.

It seems like it's taken something as silly as involving a solicitor to get you to actually sort it after 3 years.
I'd be miffed getting mail for a DC's ex.

My brother has been living out of home for four years. We still sometimes get his mail! He's repeatedly attempted to have it redirected,, but some companies are just fucking useless.