By "flake" do you mean she stood you up without a call or decent reason? That's something I won't tolerate, but whether or not you tolerate it is up to you. Did she call to tell you why she couldn't make it and have a solid reason? Or is she just flaky?
It's your life. You have a responsibility to your own future happiness to be sure a lady is who you want before you settle for just her. If this gal is not who you want, move on. If she is who you want, see if you can work it out. If we set our standards too high, we'll never find that perfect person. But if we set them too low we're guaranteed a miserable relationship. The trick is to know what we want, be sure it's realistic, then keep looking until we find it.