I've read Ama's post a few times and I didn't see anything that suggested that she was being prescribed by a GP. (For what it's worth, in my own post I referred to my "doctor", but that doctor happens to be a specialist in psychiatric medicine)

And I just want to echo Possegal's sentiments - anti anxiety/depression treatments work differently for different people. It's kind of a crapshoot, unfortunately. Part of the reason why I put off getting treatment for so long was because I dreaded the potential trial and error involved. Now, as it turned out, I was very fortunate that after a short adjustment period (namely, the insomnia that I experienced, which responded very well to sleep medication and which went away entirely within couple of months) I adjusted very well to Lexapro, and I didn't have to try any other medication. And it really has greatly improved the quality of my life.

All I'm trying to say is that if it didn't work well for you, that doesn't necessarily mean it won't work well for someone else.