The decision to go back to school and give up just about everything was the hardest one I have had to make in my life. If I can do it, you can too. Bruce completed medical school and is in a Family Practice residency in Oklahoma City. If I can do it you can too. Six of my classmates are over 40 with me being the oldest.
Life is great so go for it.
I'd like to encourage you to keep plugging away if you sincerely want to be a doctor. There are several links you might be interested in. I am currently in Osteopathic school and can tell you flat out that there is no difference in the basic medical training. I am much more equipped to see patients than counterparts at the local M.D. school. In light of that don't discount an osteopathic education.