This is the third time you've posted the same question over a period of a couple weeks. Yes, you can start the Zoloft. The St. John's Wort is well out of your system, and it was never a big problem to begin with. I think the real problem here is you're undecided about whether to take medication, and boy can I identify with you there, but if you've exhausted other things and your life is unliveable you gotta do what you gotta do.
Hang in there & please speak with your doctor. I pulled the number up for the suicide prevention hotline. If you feel like harming yourself please call and let them help you.
Here's the number
1 (800) 273-8255
Best of luck
You asked this same question before, did you ever ask your doctor? I would bet that it's just fine to start the Zoloft, but you need to check with him/her first. You need to touch base with him/her anyway, as you're getting to a crisis point.
It goes without saying that if you feel you may harm yourself, you need to seek help immediately. Update us after you talk to your doc, hang in there!