Civil Service Retirement System and Social Security

My ex-husband (now deceased) retired from the United Stares Postal Service under the Civil Service Retirement System (CSRS) around 2009.

We had been married 37+ years. Divorced in 2007. I retired in 2013 and started using SS at age 62. I was told by SS staff that because he was on the CSRS plan, I had no claim to this benefit or any additional money from Social Security. Several times I checked back with SS to see if there were any changes. I know at some point, maybe when he turned age 70, he was able to double dip, receiving the Civil Service Retirement benefit and Social Security

Once again, I checked with SS office and was told his SS check at that time was less than mine, so I had no further claim. Just doesn’t seem fair.

I don’t have a lot of hope but thought maybe you have some insight.

Thank you for this opportunity to ask for your advice.