First off, don't be discouraged! An A in orgo I and II is nothing to sneeze at, and your GPA's stellar. You've got this.
I started out like you did - tried reading all content plus note-taking (I also used Kaplan) and quickly realized it was not going to work. Bought every single practice test and question bank AAMC had available at the time and just pored through those. I referred to EK for things I needed a refresher on. Ended up scoring with a 514 - this after only a couple of weeks of actual content review.
I agree with your friends - the more practice, the better. I definitely internalized more material/knowledge and honed my test-taking skills by taking practice tests. When concepts escaped me, I'd go to EK, skim through the material and then do the end-of-chapter questions; I found a lot of material came back to me this way.
As for psych/soc, if you've taken a psych/soc class in undergrad, you'll likely be familiar enough with a lot of the concepts and can probably pull off a quick review of terminology.
If you honestly didn't retain any concepts/material from undergrad, then it's better that you discovered that now than later and break out of the habit of 'learning and forgetting'. (We're obviously all guilty of it to some extent, myself included, so don't take this the wrong way.)