Is the spouse of a retired person eliable to get the retirement pay?

The retiree's pension stops upon death, so the short answer is no. However, there are survivors benefits that the spouse is probably entitled to. Most military retirees pay into the Survivors Benefit Plan, which is a sort of annuity for spouses. When the retiree dies the surviving spouse will receive benefits under that plan. But it's possible that the retiree could have opted out, in which case the spouse does not get the survivor's benefits. My understanding is that all military retirees are automatically enrolled in SBP unless they opt out, which requires written approval of the spouse.

More info here:
The Survivor Benefit Plan Explained - Military Benefits - Military.com