At first, I thought it was really fucked up of her to do so soon after Dio's death. I mean, I'm sure there are plenty of people like me who assumed they were still married since she kept his last name. Wikipedia even says:
Dio remained married to Gaxiola until his death.
I know not to trust that site 100%, but most info is usually pretty accurate. Now that I know they were split for so long, it makes me kind of sick that she's just mooching off of his legacy. There was no need for another best of collection. Anyways, I hope she's happy with her decision.