Sexual abstinence is when someone decides not be sexually active. Being abstinent is a conscious decision that one makes and you can make it at any point in your life. You can make the decision in your teens, 20's, 30's, 40's, 50's, and so on. People have all sorts of different reasons to choose to be abstinent. For whatever reason you're being abstinent for whatever personal reasons you have, you want to make sure that you come to that decision on your own. It shouldn't be your partners decision whether or not you choose to be sexually active.