when is it enough

I often wonder how can you be in a relationship and feel like that relationship is hurting you rather then helping you become a better person. why is it that some people don't want to see throught thier partner eyes. I guess in life I NEVER really had someone to care for me as this person who shall remain nameless dose but, I feel like we spend most our time fighting then anything else. I understand that he wants to be helpful but sometimes I think he over dose it. There are times that I wonder how did i let myself get cought up in something like this ? How can i help this person relize how what he dose affect me ?