As the previous poster stated, sarafem IS prozac. And prozac is now available generic, so you should be able to get it cheaply. The only thing is, if you've had problems with anti-depressants in the past, you may still have the same problem with prozac.
Keeping in mind that it's an anti-depressant, you also have to realize that anti-depressants have to be taken every day for at least a month before any kind of changes can be seen. It takes that long for it to build up enough in your system to start seeing a difference. I suppose you should try to stick it out for at least a month or two to see how it works. But if your side effects are really unbearable, then I don't think you should continue to torture yourself.
I've heard that some women seem to have good luck with Yaz birth control pills for PMDD. You may want to check the birth control board and see what you can find there. But keep in mind also that the birth control pill has its own side effects associated with it that can range anywhere from just a little annoying to really bad, depending on how your body handles the fake hormones.