I can understand that greatly....I have had depression pretty much forever (as long as I can remember). I worked in the mental health field for many years, studied psychology and have my degree in it. Yet still refused to go to counseling myself as I saw so many people from my line who were much worse off then I and I always thought I could "handle it" or "control it".
In my belief now, depression is such an individual disorder. You dont have to have the abusive background, relationships, or general disfunction to have depression and have it impact you in a severe way. As you stated in your post, things pile up one on top of the other and in someone who has depression we tend to dwell on these things. It took me a long time to get my behind into counseling (just last yr..and I am 33 yrs old) and it has helped me greatly if for nothing else then to just clearing my mind of all the crap that I carry around with me on a daily basis. Stress.
Please dont worry about unburdening your problems onto someone else in this manner, this is what they are trained for.
I am sorry about your car... to that I can relate also! We had a huge hail storm a few months ago and I had thousands of dollars of damage done to my car (forgot to put it in the garage)....finally got the last of the body work done 3 weeks ago and while my car was at the body shop, finished and waiting for me to pick it up some idiot ran into it. Karma i guess....