I have been where you are and I know the frustrations, I’m 69. My experience has been that I tolerate Paxil very well, been on it since 1998. After a traumatic brain injury in 2008 I was on 3 different SSRIs at the same time. After the suicide thoughts became too much I quit cold turkey on all three. After the withdrawal I was back to depression, anxiety and PTSD. Went to a new psychiatrist who put me on a low dose of Paxil since I had tolerated that for 10 years, before 2008, and it worked. I have had to increase the dosage over the years and am now on the highest recommended dosage, that kept most of the bad stuff at bay but still would get bouts with the depression, anxiety and PTSD. Then one day, just this last summer, something changed in my brain and I am free of all the bad stuff, prayers answered!
What I am leading up to is, if Prozac worked for you 30 years ago, it may work again, as johnhans pointed out you may need a higher dosage and it may take a little longer for it to kick in, a month to 6 weeks for full effect. The initial side effects could be a little difficult too, as each time I increased dosage I got the usual side effects I always get but after a week or so they were gone.
That’s my 2 cents worth, God Bless and keep o going!