Selfless Sacrifice

Did you ever have to make a choice between something that was good for you and something that was good for someone you cared about? 
I really hate making choices, because you can't predict what would happened next and people often have to face the consequences of their own choice, even if it is a very easy and basic decision. There was one time that my friend and I went to a bicycle camp. We basically rode bicycle everyday and to different places. We all had a water bottle with us. The coach told us in the first day that don't drink to fast, or else we would run out of water. Because normally there was no place for us stop and fill out our water bottles in the middle of the trip. But my friend didn't listen to the coach, she kept drink her water. Her finished her water half way through the day. She asked me to give her some water. Even though I know that If I share her my water with her, I would probability be thirsty later, because the water was not enough for both of us. As a friend, I shared my water with her.