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I am very sorry to learn of this situation, and I do hope that your wife is okay.
Unfortunately a finding of liability by the CHP does not mean the same thing as a civil finding of liability (so there is no enforcement, there is simply enough for the other driver to be cited with an infraction - which they have an opportunity to challenge in traffic court).
What your wife and her insurance carrier will need to determine is whether or not it is worth filing a civil lawsuit against the other driver.
A civil suit would be defended by the other insurance carrier, and these lawsuits can drag on (it really depends on the other carrier and how unreasonable they are - good carriers would simply pay a claim when the liability is as clear as what you describe yours, while bad carriers will force a driver (such as your wife) to go through written discovery, and oral depositions).
However, in the meantime, your insurance carrier should be providing you with compensation under the terms of your insurance policy. There are only 2 reasons to pursue litigation like this (1) to reimburse your insurance carrier (you have a contractual liability to cooperate if your carrier decides to do so); and (2) to gain compensation if your insurance policy does not cover this loss (this is going to be decided entirely on the terms of your specific policy).