Underestimating people is almost always a mistake: and that's especially true in your case. So why not stop being so hard on everybody else (and, ahem, yourself) and give 'em a break? It's all a matter of having expectations and managing them sensibly. For instance, if you expect to fail, well, very often that becomes a self-fulfilling prophecy. This time, why not expect much more from yourself and those dear to you?