My best friend and I ended our friendship a few months ago because we had a strong disagreement about something. I miss her a lot and wish I could fix what happened but know there is nothing I say or do that can make her change her mind. I want to wait for a while and see if time makes her more mellow and open to a conversation, but she has blocked me on all social media and doesn’t even respond to messages sent to her via common friends. I want to apologise just to make this better even though I know I was in the right and that she is the one who needs to apologise. What should I do?
You should wait until she reaches out, if she chooses to, given that you have tried all other means of communicating. If she isn’t responding, it’s because she’s not interested or nor ready to have a conversation. As for apologising just to fix this, you should consider it only if you genuinely want to put this behind you. If you do it for the wrong reasons, this issue won’t magically go away, and may come up the next time you have an argument. Friendships evolve, and sometimes fail when two people go down separate paths. All you can do is hope that your friend has a change of heart and considers reopening a dialogue with you.

There is a girl I like who constantly flirts with me, but never lets it get to a serious point where we can talk about our feelings or what this means. She says she likes me but doesn’t want to date or talk about a relationship. Is she just playing with me?
If she isn’t ready to have that conversation, why not give her time and space instead of jumping to conclusions? You have told her how you feel, and it’s possible that she needs to get to know you better before she understands what her own feelings towards you are.