my truck was parked on the street. a car came and hit it. her insurance only wants to pay 1/2 of the damages. can i sue her.

Your question provides insufficient information to provide a meaningful response. Generally, you may sue a negligent driver to recover property damage, the measure of the damages would be repair costs and loss of use, and the amount of damages may be reduced by your comparative fault, if any. You do not mention if you have made a claim on your own automobile insurance policy, but if you recovered damages your carrier paid for you may have to reimburse it. You should consult with an attorney to discuss the particulars of your matter and for any specific legal advice.