How many times do you text someone without them replying before you stop sending messages? How many times does someone have to text you without a response before you snap!?
My basic rule is, say something like "Hey whatsup?" and then DONT SEND ANYTHING ELSE unless its something important. If you are being conversational, there is no reason to send over 2 messages. Usually if you send me "Hi", I will reply when I feel like talking.
Don't send me texts increasing in immediacy demanding me to talk to you or asking where I am!! After it becomes "Why aren't you texting me, are you ignoring me?" I'm going to actually start ignoring you.