MK, I can relate to your feelings. I always felt like I was never going to be good enough, like I was a disappointment. Now as an adult, I know that's not what my parents wanted me to feel. They thought they were being obedient to the Lord....but whether or not it's what they WANTED to teach me...it's what I learned! I learned that having needs was selfish, that it was not okay to not be okay. I was told that I represented my parents ministry, when we went to visit supporting churches, etc...and that is a LOT of pressure for a child. Every mistake I made felt like the weight of the world. I felt responsible for things that are an adult's responsibility.
My parents left the mission when I was a teenager. We went home on furlough and never went back. I always thought it was my fault, because of the abuse that happened in the dorm, and I just "couldn't get over it" and needed help. Just a few weeks ago, I was finally able to share with my Mom that burden of guilt that I had always felt...and what a relief to discover how wrong I was. My parents hadn't even known the weight of responsibility I had felt, didn't even realize that it had been communicated that way. There were other reasons they left the mission, and me needing help was NOT the burden I always perceived it to be.
I wish I could say I came to these brilliant deductions about my childhood on my own

...but I have been very blessed with a fantastic counselor who has helped me learn so many things that I believed that weren't true. It's such a hard process, but it feels like freedom to me!
Can I recommend a book? I like to read, and the book Boundaries, by Cloud and Townsend, has been SO helpful to me.
Praying for you.