Indiana Code Title 29. Probate § 29-2-19-15

(1) dissolution of marriage;

(2) annulment of marriage;

(3) legal separation of the declarant and the declarant's spouse;  or

(4) court determination that the declarant and spouse were physically and emotionally separated at the time of death and the separation was for an extended time that clearly demonstrates an absence of due affection, trust, and regard for the declarant;