@jsn1711 I, too, had extreme withdrawal symptoms after two months off venlafaxine. I presumed I decreased too much too soon, and went back on the drug at a reduced dose. I am now tapering more slowly. The Maudsley Deprescribing Guidelines suggests two approaches for "Management of protracted withdrawal syndrome":
"Limited research and clinical experience suggest people do recover spontaneously from protracted withdrawal without specific intervention, albeit over sometimes long periods. So, a conservative approach to management may be reasonable. Patients often require reassurance that they will improve in time. They also need support...if such states are prolonged, as they can sometimes be debilitating.
"The second option is re-instatement of the original medication....However, when there is a longer delay in re-instatement after the onset of withdrawal effects (e.g. months or longer) the response is less certain." (Page 54.)
I have been where you are, in "sheer terror for no reason." That was after two months off the drug, I did not know what was happening (was unfamiliar with the dependency this drug causes), and didn't feel like I could cope, so I opted to return to a reduced dose and taper more slowly. In your case, since you have days that you feel fine, and you are already eight months out, you may be more apt to "recover spontaneously." In my case, mornings were the worst but I found that physical exercise helped more than anything. What if you went to the gym on those days that you didn't feel like it?
I recommend Mark Horowitz's information online and The Maudsley Deprescribing Guidelines for more information. All the best to you.