Okla. Stat. tit. 43, § 43-130: Evidence

Upon the trial of an action for a divorce, or for alimony the

court may admit proof of the admissions of the parties to be

received in evidence, carefully excluding such as shall appear to

have been obtained by connivance, fraud, coercion or other improper

means. Proof of cohabitation, and reputation of the marriage of the

parties, may be received as evidence of the marriage. But no

divorce shall be granted without proof.