interesting, your experience with Lexapro mirrors mine, it was difficult to get onto this time when it was no problem before, and then I switched to pristiq but added back 5 mg of Lexapro 2 weeks ago. Klonopin has been helping me get thru all of this, and the pdoc did add mirtazapine too, but I could not get up to 15 mg, half a pill is as much as I can stand. Don't know why, it just makes me more anxious and depressed when I tried to raise it twice. Ditto for the pristiq when I raised it, which means doubling it b/c the morons who made it did not make a 25 mg pill and its time release so its hard to raise, lower, or go off of it b/c there are no small increments. The one time I tried Prozac it was way too stimulating for me, and it wasn't 40 mg, which I think would be a decent amount, if it works for you, but your own experience is your best guide. As for buspar I tried it a year ago, again a low dose, not sure what it did, if anything, but for some it works. It also is supposed to boost other antidepressants.
When you find something that works, probably best to stay on it to prevent relapse, none of us want to be on medication but the chance of relapse is raised if one goes off of it.