In Alabama, the statute of limitations on torts is 2 years, this means that you need to file suit against the at fault driver within 2 years of the accident. 
If the insurance company is offering you an unfair loss in value amount, you need to hire an independent appraiser to rebut their valuation.
You can also escalate the claim by contacting the Alabama Insurance Commissioner.
Insurance Bad Faith in Alabama
Citation: Ala. Code 1975 §27-12-24
Title 27: Insurance
Section 27-12-24 – Refusal of insurer to pay or settle claims
No insurer shall, without just cause, refuse to pay or settle claims arising under coverages provided by its policies in this state and with such frequency as to indicate a general business practice in this state, which general business practice is evidenced by:
(1) A substantial increase in the number of complaints against the insurer received by the insurance department;
(2) A substantial increase in the number of lawsuits against the insurer or its insureds by claimants; and
(3) Other relevant evidence.
