Would you elaborate at what you mean here? Two reads I have are either (a) you're getting at whether feelings like this are subjective, which is true definitionally but seems to me to be uninteresting, or (b) assessment tools (such as the Beck inventory) are imprecise, which is also true, but can still provide some basis for comparison. Or something else that I'm missing?
That said, I would like to see a longer time scale to see if the changes are maintained.
In any case, looking back that 8 weeks and comparing to now, _after you've just been through 4 weeks of hell_, you'll report that you're feeling a lot better, even if you've only returned to the same level you were before starting the meds.
Are there studies that use family/etc as the basis for their data? That would be a lot more valuable, as long as they also include a control.
The studies also need to look a lot longer than 8-12 weeks, partly due to the onset side effects, but also as a lot of depression is caused by a stress event that passes and resolves in a few months. It is interesting that a placebo has a positive effect (not as large as the meds); I wonder if they measured the effect of no treatment at all.