I am in my 70's and my fiancé is in her 60's. We are both retired but she has a very small income to support herself and we mainly live on my social security income here in the Philippines which is well above average but still does not allow us to live the retired life we would like to. Our plan is to get her US citizenship in the 3 to 4 years required for a spouse to live in the US so that she can continue to collect an additional 50% off of my Social Security even after we return to the Philippines or wherever we decide to live outside the US. Also, if I were to pass while we are living abroad she will be able to collect my full Social Security.
At the present, the processing time for a CR-1 spousal visa 12-16 months and the time to process a K1 fiancé visa is 4-7 months. I know it doesn't sound like much, but when you are our age, 6 months to a year is a long time to wait before we can start really enjoying the active retirement we plan to live until we are physical unable to do so.