Mental alertness symptoms and conditions

I started on zoloft about 11-2006 i started of on 50mg and was increased to 200mg daily, it's been able 8months the side effects that I have had weight gain, skin rashes, nightmares. Then 8 months on all of a sudden i started getting moody, verbalily an physicalily aggressive, snappy, unable to think clearly, remembering normal things like names, loosing things, no time for anyone or thing, no focus on things being said, zoning out of my mental alertness, nerves always on edge, headaches, sleepy, a sense of fear, depression. Coming off zoloft just heightened the side effects. I was placed on zoloft due to PTSD and major drepression.