If your goal is to achieve your dreams, to become a better version of yourself, or to simply just be happy, I encourage you to let go of shame, regret, resentment, anxiety, and anger. Leave those unhealthy emotions behind in 2014. By doing this, you'll truly start 2015 with a clean slate ready for prosperity.
When it comes to taking full responsibility for your own experiences or taking none, there's a continuum. Some of us blame our circumstances and our feelings on the external world and other people. Some of us actually take too much responsibility for our "stuff." Despite my anecdotes above, I have realized I'm on the too much responsibility side of the continuum.