Doctor Answers (1) on Depression
Your self esteem issues, you not being able to speak up may be related to social anxiety you might be suffering from. I can't comment on whether it's to the extent of calling it a social anxiety disorder, without knowing the details.
Secondly, your lethargy and your difficulty with disscociating from your 'big failures' might say about your personality or it could indicate a temperanent issue or even depression, possibly.
I, however can coment only so much with the information that you have provided. So, whether you need help or not, can only be decided with a detailed consultation with a Mental health professional.
So my advice to you, why not get it clarified from a professional, if it has been affecting you all this while. Go for a consultation.