Insurance wants to total my car

I did get a second opinion and they said most of the damage is superficial. The plastic bumper came off, the front rear view mirror is broken, one wheel and tire need to be replaced, one headlight to be replaced, otherwise just scratches on paintwork. I was driving about 4 miles per out and I hit a garage door that was flimsily made with the right front side of my car. The second opinion said that there is no damage to the frame and it basically needs to have the broken items replaced and painted. I am now concerned that I will be unable to get insurance.