Missouri....My ex and I divorced over 5 years ago and neither of us has remarried. If he dies, do I have access to his social security or job pension?
You can claim social security benefits when you retire, against either his credits or your own, whichever gives you the best result, as long as you were married at least 10 years.
He does not have to be deceased for you to claim the benefits, nor does it diminish his benefits.
If you have minor children, they would be entitled to social security survivor's benefits should he pass away.
Other than that, you have no claim.