If you've had some good and bad dating relationships, you can write a personal essay on these experiences and what your goals are regarding marriage one day. For example, you can discuss your frustration with some young men who are emotionally immature and won't grow up, and how this caused you to become disappointed in your past relationships. Or you can talk about recent studies that pertain to why some men won't settle down, and link this to your dating experiences.
If you're a volunteer with a local nonprofit organization, you can write a personal essay about your volunteer work and discuss how this shaped your views on the less fortunate in your community. For example, if you prepare and serve meals at a homeless shelter in your neighborhood and you also help the shelter's residents find jobs, talk about how this helped you choose a career in social services.
Another idea is to write a personal essay about how your family influenced your outlook on life as a student. For example, if your father owns a pharmacy and you learned the importance of customer service and commitment while working at his store as a cashier in high school, you can talk about how you applied those skills to your studies. Or, if you know someone who has triumphed over an accident that left her partly disabled in some way, discuss how this caused you to have a greater respect for people with disabilities.
You can write an essay in which you describe certain personal goals you want to achieve before leaving college. For example, you may discuss your desire to get new hobbies and spend less free time watching television or playing video games so you can be more well-rounded as a person. Or, one of your goals may be to be more involved in political and social causes, and you can write about how you'll do this by voting more often and researching various issues that affect you and your community.