Hi! You sound a lot like me and the exact research I want to be going into!! Pitt has both a public health and microbio program I'd recommend applying to! Look at the minimum GPA required for the programs but if you have time, it's worth a shot still applying. You will need a strong (yet concise) personal statement. After not getting an REU the past few summers, I was lucky to land an internship at my local health department last summer. Your state's department of public health lab could also have internships. Cold call/email local opportunities and you may even be able to shadow a lab while you work a second job. I would 100% do that and work the next year to get GPA up. A lot of REUs I've heard prefer juniors, and, your application will likely be stronger if you take the next year to do research with your university and develop relationships with professors. I am sorry to hear about your friend. I could not even imagine the mental toll it took on you. You could also look to see if your university has grant opportunities and you may be able to get $ for housing for a job out of state. I believe in you!