[TeMPOraL]

It depends on the person and I guess on the particular SSRI as well. In my case, I could (and did) go from normal dose to zero immediately, and I wouldn't notice any difference until few weeks later when my average mood and productivity started to visibly deteriorate.

Anyway, SSRIs are relatively safe - that's why they're deployed as entry-level antidepressants. There are many "heavier" options available. Getting on an SSRI is far from last resort.

[stordoff]

Withdrawal and dependence varies massively from person to person as you say. I had been taking Tramadol (an opioid) at the maximum allowable daily dose for close to a year, and was told to stop by a new consultant. He told me it will be "hellish" and "worse than quitting heroin"; I stopped taking it immediately (without tapering), and the only effect was the return of the original pain.