My cousin (my abuser) always had a bigger penis than me, I never started feeling inadequate until I was 16 or so when I began to realize he'd probably always be bigger than me. And maybe I thought that's why he was always the dominant one, that and he was always tougher than me. I have an average penis size, but it doesn't alleviate me feeling inadequate. So much so that it causes me anxiety induced ED, if I had a partner with a bigger penis than me it would definitely make me feel inadequate and intimidated.
"The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein