"Dave" wrote
This past september my docklines broke during a gale sending my Holder
20 sailboat into the neighboring powerboat cause about $5000 in damage
to the powerboat. A claim was filed through my homeowner's insurance.
The claim was rejected because my insurance company said that this
was an act of god and I was not responsible. ......

If your insurer is correct then God is liable and the PB owner should sue
her.

OTOH, if a court rules that you ARE responsible then I'd think your insurer
would have to pay.

Check with your state insurance commission.