This is rather a question of what can I do? Will it be possible?

I graduated with a very very low GPA.
I have thought about whether I can go to a med school for the past two years. I just ended up finding out it is my true passion and I am seriously eager to pursue this path. So, I am trying to figure out the way to boost my GPA up. May I ask for you advice about my future plans for applying to med school? Here is what I have on my resume so far...
I have not taken MCAT, yet.

-GPA 2.9 (suffering from depression wrecked havoc in my 2nd term of Sophomore and 1st term of Junior year, I had to drop all the classes in my Junior year to focus on curing this condition)
-misc. school activities which involve common volunteer works; was an officer "Webmaster" (4 yrs)
-a medical volunteering trip to Costa Rica & Panama (10 days)
-Volunteering at a hospital front desk (40 hrs)
-part time research assistant (2 yrs)
-one undergrad research grant ($1,000)
-part time lab prep member(something like a research asst) (4 yrs)
-biked across 2 countries (~4,000 miles) for cancer research, raising $4,300 (about 10 months prep & actual biking)
-2 publications from one of the best cancer institution (not first or second author)
-Research Assistant I, where I did 2 publications (1 yr)
-Peace Corps 2012-2014 as a Community Health Educator (I am leaving in March 2012); my original plan was to leave in 2010 but this was involuntarily postponed due to the recent history of depression.

I am planning on studying for MCAT while I'm serving as a PC volunteer abroad. I forgot almost everything I learned in pre-med classes... and being a PC Volunteer, you have to be able to deal with boredom. So I think the two years will serve as a great opportunity to study for the MCAT.

The problem is when I come back. I thought about this realistically, and my GPA is just unrealistic for getting into a medical school. I am thinking about taking GRE before I leave for the Peace Corps, so when I come back, I can at least apply to a public health, tropical disease or a international health master's program as a back-up plan. But I really do want to avoid another 2 years in school if I can. I am already 27, and when I think about it, I'll be over 40 when I can practice for real. Yikes! That's why I want to hear from you guys if it would even be possible to skip getting a master's (or post bac).

If you think I have to go to grad school, which would be a wiser or a better plan? Post Bac or Public Health? (My passion is in serving under-served population, whether it is in US or abroad..)

Thank you for your time.

 

I think the condition was still going on even before I noticed and decided to withdraw from all my classes during one of the semesters. So my grades were generally going down starting later sophomore year.

This might be a myth, but when I did a little bit of research, DO had some restrictions compared to MD's. My ultimate goal is to work in poor areas, especially in developing countries. I don't think DO will be as free as an MD in regards to where you can practice. I shall look into more details to this, though.

Thanks.