I feel like I have been living a life much like yours, Scoots5012. After struggling so much through the early half of my life, I was compelled to succeed if just to prove that everyone else was wrong and to somehow show them up. I became so obsessed that even a perfect score wasn't enough. I had to be perfect at everything.
It never really fixed my internal pain, however, and I gave up much of what would make my life a REAL success for this false sense of accomplishment, like feeling close to someone, sharing all those great ideas with others and building a real relationship with my family (the ones who I was trying so hard to disprove by my success).
Having reached many of my life goals, I am able to look back and relax about messing up. Getting bad grades is not so bad. It can actually come as a relief that you don't have to worry about messing up your GPA anymore! You can still try to stay focused, but remember that these pressures on you (both internal and external) are transient. I encourage you to try to think of the worst thing that will happen if you if tomorrow does bring something bad. I think you will find that it's not so bad after all. You WILL recover and someone will still care for you.