I've hit a skill plateau

  (Edited: )

Hey all, I am a silver level Terran in need of some advice.

Basically, I've been stuck in silver for weeks, with no sign of major improvements. I just can't seem to get past the top 25 level of my silver league.

I made it to where I am now by passively out-macroing my opponents (I know, not saying much). This works fine against bronze players and low-level silver players, but it fails against high level silver and gold players of all three races. I am almost always able to hold my own in the early and mid game (and in the instances where I lose early, it is usually easy to see what went wrong and adjust), even against cheese, but they usually whittle me down slowly, but decisively, in the late game. 

I have a really hard time figuring out what I need to adjust and what I should focus on. I feel like my being overly passive is part of the problem, as is my inability to gain map control or punish their greed, and being outplayed in the late game combined with inability to ever gain a decisive advantage in the early or mid game (or even win at those points) but I really have no idea. Any tips/thoughts would be appreciated!

Edit: Here's an example I posted down in the conversation of ZvT where the zerg pins me down: http://drop.sc/306379