@wl4596
I think you might be falling between some cracks here. But there may be some ways forward.
1. @ReTiReD51 gave you one way
2. It does sound like that whatever your benefit amount from Social Security covered work might be adjusted with the Windfall Elimination Provision most specifically your 30 year work with the fire dept. if they did not participate in the Social Security system - some state / local government employment don't participate.
If that is the case, whatever Social Security benefits to which you are entitled - your own or spousal is gonna be reduced based on the Windfall Elimination Provision (WEP) of Social Security.
3. You aren't gonna be able to file for divorced spousal benefits under the earnings of your ex-wife because you got married.
4. However, if your current wife is receiving Social Security Disability (SSDI) Benefits and NOT SSI (Supplemental Security Income). Under the SSDI program there are family benefits. Read this SSA page to see if you are eligible for this program; but again - even your benefit under this Family SSDI program will be reduced by the WEP.
SSA.gov - Social Security Disability - Family Benefits
Hopefully, in one of these ways you will be able to inch out a few bucks to pay your Part B premiums - IF you are lower income, you might be able to get some help even there. This Medicare link describes the eligibility and the help
Medicare.gov - Medicare Savings Programs
It's Always Something . . . . Roseanna Roseannadanna