Effexor hell - side effects or withdrawals?

I can't tell the difference and my psychiatrist doesn't seem to have a clue either. I'm incredibly aggravated.

Has anyone else experienced the phenomena where they start experiencing intermittent symptoms after taking pretty much the same dose for a year or more? I've been taking 100 mg Zoloft and 225 mg Effexor for almost two years.

For the past year-and-a-half I've noticed constant drowsiness and vague chills / malaise. Now in the last 6 months I've started noticing a weird nausea-like feeling that comes and goes randomly. Unlike normal stomach nausea the feeling also exists inside my limbs. It doesn't make me vomit, but its horribly uncomfortable and makes me feel restless and tired at the same time. All of this is accompanied by worsening depression and anxiety.

My psychiatrist thought these sensations were delayed side effects. Has anyone had new side effects appear after being on the same drug for years? If its a side effect, decreasing the dose should improve the symptoms, no? Experimenting I found exact the opposite. The symptoms go away when I take more and get worse when I take less. My psychiatrist refuses to prescribe a higher dose and insists I'm experiencing side effects, not withdrawals. Yet I try to taper down and everything gets worse, not just a little worse, MUCH WORSE, and not just the depression but the supposed "side effects" as well. I basically feel like I'm a cancer patient on chemotherapy. Everything exhausts me and I feel tired and sick for no reason. I feel like I'm dying. I'm also emotionally volatile with extreme fear, anxiety, and anger that comes out of nowhere in waves. The only breaks from feeling exhausted are when I'm feeling like I'm going to explode. It feels like I'm teetering on the edge of an infinite abyss that could devour me whole.

I think I've developed so much tolerance from taking antidepressants for so long that they basically made the underlying depression worse while covering it up with increasing doses and somehow altered my brain so I feel both physically and mentally sick without the drugs. It seems psychiatrists refuse to believe that this can happen to some people. It's similar to how they refused to believe withdrawals existed in the 1990s. It fills me with rage. Has anyone else had to deal with this? I feel trapped and frightened. I don't trust my psychiatrist. I don't trust any of them. I feel like I want to punch them in the face. I screamed into her goddamn answering machine because her voice on the recording annoyed the ###$ out of me. She called me back and told me to go to the ER. Screw that. I just took some Atavan to calm down. I wish I had never gone on this garbage.

This all happened yesterday. I feel marginally better today only because I increased my dose back up to the normal amount. Problem is I STILL notice the symptoms, albeit in a milder form. This is on the dose I've been at for two years. So whatever underlying sickness this is has gotten worse to the point where the medication is no longer able to mask it.