I was on Paxil for 3 years and the withdrawal took me 1.5 years. I went faster than I should and I could feel each and every dose reduction the next day with extreme bouts of nauseau, fatigue, etc. I am convinced that Paxil withdrawal played a fairly decent role in me having CFS today. I was stubborn and overconfident and thought I would recover, but I never did and wound up with CFS after my withdrawal (note there were other factors like mono, etc.)
If you do not have a long-standing depression or anxiety problem I would not take SSRI's; especially one's like Paxil and Effexor which are known to have severe withdrawal symptoms. In my case SSRI's never helped my depression only my anxiety. They actually worsened my depression because they dulled my ability to feel any emotion at all.
I would encourage you to try CBT or other forms of therapy with a therapist. I know CBT isn't popular around here because it's touted as a CFS treatment with no actual scientific basis, but when it comes to depression and anxiety it really can help. It can teach you means to reframe your thoughts and to cope with your ongoing issues.
There are also relatively risk free supplements (compared to SSRI's) like Fish Oil, B12, SAM-E, Vitamin D (Note: all of these can be riskier for those with CFS). Make sure you try one at a time for at least a few weeks to accurately gauge their ability to help your depression. All the supplements I listed have studies showing efficacy with depression and are worth giving a go before subjecting yourself to a potential longstanding withdrawal with SSRI's.
With that said, if SSRI's worked to resolve my depression in the long-term I would take them again in a heartbeat. The biggest difference being that I have had issues with depression my entire life rather than having it directly associated with recent life events. If my depression was only caused by recent events I would never touch a pharmaceutical; it just isn't worth the long-term repercussions if you can cope with it through other means.
I could be wrong as I am not everyone, but I don't really think most people understand how bad severe depression can get. You quite literally spend every single second in absolute agony, misery and emotional turmoil to the point where the only thing you want to do is off yourself to make it end. If there was a pill I could take to make sure I never go through that again I would take in seconds even if it meant it would take 10 years off of my life. That pill doesn't exist though

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