I have been called a perfectionist at times, always trying to achieve high standards without flaws. Do you also experience this or know someone who does?
I did when I was much younger. As you grow older, you kind of change your mind on that...
I can understand why - it has its downfalls especially when attempting to achieve unattainable results in your life.
Yes, exactly! No one is perfect, so you have to roll with the punches and accept things for what they are.
It is hard though since I always perseverate on certain goals and often measure my worth based on obtaining them. 
Goals are great, but you must base them on being obtainable. You can't fool yourself.
That is the other hard part too. When I do not achieve goals, I often am my harshest critic making me want to find a new goal and start over.
Starting new goals not the answer. You need to complete a goal then create a new one. Otherwise, turmoil!
I agree, but I get so much pleasure from obtaining my goals, realistic or not.
Well, then keep doing what works for you.