It sounds like you may be dealing with what they call complex PTSD, which is a relatively new disorder that hasn't been included in the standard DSM IV yet. It's like PTSD only it's got slightly different symptoms and it's born out of long term trauma (such as abuse) rather than short term trauma. One symptom that it does share in common with PTSD is flashbacks. In a flashback the emotions/memories of the original trauma flood you even though you're in a different and safer situation than you were in the past.
Growing up in an abusive environment also sets one up with certain limiting beliefs that can later make life a lot tougher for them because these beliefs perpetuate the cycle of abuse they have known.
It is very important that you seek out some form of professional help with this as soon as possible. The longer you wait the tougher it gets to recover.
I was abused while growing up as well. I tried every trick I could think of to recover from it on my own, and even believed for quite a few years I had recovered from it and blamed myself for the continuing abuse in my life. I learned the hard way that you CAN recover and you are the only one that can do it BUT you have to be equipped with the right tools to be successful... and when one grows up in an abusive environment, the tools they are given are few, mismatched, and mostly broken. With counseling you gain a good set of tools to accomplish the work you need to do in order to recover.