Just providing some clarification...I talk to people about these scenarios in my line of work.
If the widow (widower, as well) is over age 60 and remarries, she will STILL be able to receive survivor ssi.
If she is under 60, and remarries, she does NOT receive the survivor benefits.
The are some exceptions around the age threshold if she has younger children, a disability, etc.
If the root of her concern is about planning for income, it might be worth it to seek out professional investing advice, overall professional financial planning advice, OR really take time out to educate herself on investing for income, particularly if she is a long way from 60...i hate to see anyone have to prioritize important life decisions based on how much ssi they will receive, there's so much more to life, no?
praying, brother.