Lots of college students and young people living on their own eat like crap. Just own up to it, no excuses. Some people are pretty empty pocketed at this stage in their life, which is understandable, but no one can stay healthy on ramen and tap water. I like to budget thinking that some of my monies destine to entertain myself get added into food. I kinda find some zen in cooking for myself, and get healthy and tastey results. Well… at least vegetables and identifiable protein sources are involved kinda healthy.
If you were never taught how to cook at home, it might seem like a high mountain to climb. But you can always start with a basic cookbook, and just start making things that sound good to your tummy. Here is a great list of cook book recomendations from the NYTimes (free to sign up for if it prompts you for a log in). Steal/beg/borrow from the library, scrimp and save, just please for all that is tasty avoid eating ramen more than twice a week.