Ugh

Some of my friends stink. Let's say I told my one friend (call her A), about the boy I like. I trusted her not to tell. Then she told my friend N and then N told K. At lunch the other day, I sat w/ N, K, and C. I didn't want C to know anything but then K blurted something out about him. I was peeved. What do I do? I feel like I can't trust anyone :(