My ex-wife kept my name, too.
In my case, it was somewhat different because we had children who bore my name. I suppose keeping my name allowed my ex to avoid questions. She may have had other good reasons.
Still, it didn't keep me from feeling some resentment about it.
If I wasn't good enough to hold on to as a husband, why was my name good enough for her to keep?
She's re-remarried ow, and taken on her new husband's name. Although we remain friendly, somehow it feels as if the divorce is finally complete.