So frustrated

GRRRR
Ok...this makes no sense to me. Be aware that I am still irritable and cranky from the increased wellbutrin and I think I am maybe a grouchy person to begin with lol.
We had the same car insurance company for 20 years. Well, my husband had them for years before we got married and then when we got married he added me to his and we even used them as our homeowners insurance when we bought our first home. The rates kept rising though and even though Ray or I have ever had a ticket or an accident it just kept going up. We decided to shop around for insurance. We found a few that were pretty close in rates and then another one that was a bit more then the other estimates but the insurance agent was very friendly and helpful so we decided to go with that one.
We have had this new insurance for over 2 years now. Ray nor I have had any tickets, any accidents, any claims, no new vehicles or anything. I drive very very little...like maybe 300 miles in a year..We got a letter in the mail a month or 2 ago that said they were going to start doing credit checks and adjusting rates based on that. Well, we assumed ( yes I know what they say about the word assume) that it meant they would look over our payment history etc. I mean why else would they need to do a credit check?
After over 2 years of paying our payment on time every single month, never bouncing a check, never a day late, never a claim, they thank us and reward us by charging us an extra 500 dollars a year because our credit record was bad...Yes it may have been bad, we had some trouble a few years ago when I was not able to work anymore and before I started getting my disability check. BUT, it never affected us making payments to the insurance company. Our credit now is in the same state it was over 2 years ago when they first started covering us. NOTHING has changed to make us a higher risk except for the fact that they ran a credit check. How does the fact that we were late on a SEARS credit card affect our ability to drive?
I see no correlation between our credit and our insurance rates. And even if they did want to raise the amount because of bad credit, 500 dollars a year seems very excessive. I mean we could get in a wreck, cost the insurance 1,000's of dollars and our rates would not have gone up 500 dollars a year.
I do not think this is fair. We are being punished when we have not done anything that would warrant the need to charge us more.
I am sooo irritated and upset. 500 dollars a year may not sound like much but for us it seems to be quite a bit. We budget, we buy food on sale, we do not use much gasoline, I leave the cooler set on 80-82 degrees even though I would LOVE to run it at 75 and then BAM out of the blue for no reason we are charged an extra 500 dollars a year.
I called the local insurance agent, of course he is NOT in. I talked to the poor assistant for over 20 minutes trying to understand how they could justify doing this. I guess they do not need to.They just do it and we either have to pay it or not have insurance. She did give me another number to call but right now I am too upset to deal with somebody else and I am sure it will not get me anywhere.
I know life is not fair ever but this just seems wrong. To me it would be like trying to apply for a credit card at SEARS and having them check my driving history. How does one relate to another??? Maybe the insurance company should run a check on my library card as well and charge me more since I was late returning a book...that would make almost as much sense to me.