Most Helpful Girl
It might be weird for some simply because people much older than you have grown up in a different era and may have experienced things differently (like high school, finding work, etc.) than you have. If you get along great though don't worry or let what other people think bother you. Knowing lots of people who have had different life experience than you is a great way learn more about the world and to grow as a person.
Most Helpful Guy
Women will generally be upset when men their age are dating younger women. Personally I don't find it weird love is love no matter where you find it. However the larger the age gap the likelier you'll be at different stages of personal development, and may find irreconcilable differences. Children and marriage are 2 major hurdles that can and likely will come up. good luck to you whatever you decide.