Flaws

When someone points out a flaw in you? And I don't mean like a snag in your sweater... I mean like a character flaw. Do you get defensive and say no way? Do you get defensive but wonder inside if they're right? Do you automatically think they are right?Someone pointed out what they see as a flaw in my character. At first I was pissed off, and started thinking of a litany of excuses and reasons... and then I stopped. Because I started realizing they were probably right. They said that emotionally I'm either really good, or really bad... never just middle of the road. Now I'm gonna qualify a little and say "never is a little strong" but the general gist of it is right. So now.. what do I do about it. How do you be authentic and tlel people what's really up with you? Does this mean I should always be up? Always perky? Always sunshine and smiles? Does it mean I go through what I go through and deal with the crap but keep my eye on the good things? Does it mean that some people get to only see that side? Does it mean that maybe one or two people get to see all the way in? Is that fair to them? Isn't life about ups and downs? Do I let them show too much? But then I also have people telling me to never change who I am.Hmmmmm.........