Should i feel really bad, or be really mad?

When you’re going to meet someone, to give them what they’ve been asking for for a while, then they ditch you, how should you feel?

What if after words you ignored them, but they became depressed because of that?

What if you finally give in, because you can’t stand seeing them like that, then they continue treating you the same way?

Do you feel mad because you were stood up on something important they asked for? or Because you gave them second chances and they mistreated them? or Because they made it about them… again…?

Or do you become sad because you can’t stand the fact that you’re the reason they went into depression? or Because you feel useless and pathetic? or Because everyone gives YOU shit about it, even thought it’s completely their fault…?

I’m so confused right now. In person, she seems to really care. But over text, or on Facebook, she couldn’t care less. I need help.