All I can say is grow up. It's only texting, sheesh. People don't have to be at someones beck and call 24/7. So she doesn't return a text, are you really that paranoid?
You know how stupid you sound right? If you are texting that would mean you are using a cell phone. Why not call her instead? Like actual talk you know? If you want communitcation then call her if you can't be with her. Texting is so impersonal, just because it might seem almost everyone does it, not everyone likes it. Maybe she is one of them. It seems you have some insecurity problems, and I would try and get over it.
Again, call her. Use your voice. Grow up, you sound so young, maybe it's just your immaturity. Don't knocking you down, you just need to realize texting is not really a way of keeping in touch. Actually being with people is how you keep in touch. When you can't be with persoanlly with other people we use something called the Telephone. Now we have cell phones to be more convienent. Funny thing is, people don't acutaly use the cell phone anymore to talk to people.
Look at my sig. I read it here on the BSF and laughed so much I had to sig it.
Holy crap, did someone take a dump in your breakfast? Is anyone ever this blunt when you make various threads asking questions that could easily and quickly be resolved with a Google search? No, because we're here to help you with things you don't understand and we're not gonna be mean about it because we're all at different levels of understanding.
Anyway, I can see why the OP might be a bit irked about this habit, but it shouldn't be anything to worry about unless this is a sudden change or she is defensive about not telling you what she is up to. If you've just started the relationship, you will go through growing pains where they will do things you don't quite understand yet and they will seem strange. Like when I first began talking to and getting interested in my fiance, he would say "anyway" a lot. For example, he would mention something and I would make a joke about it and he would laugh and say "anyway," and continue. The way I grew up, it's extremely rude to say that because it comes off as you not caring about what the other person thinks and I would get people doing that to me a lot. After he and I finally admitted we liked each other and even when we didn't know for sure but were suspecting it, I grew to learn that he didn't mean it in a rude way; he just was raised with that speech habit. I'm glad I never confronted him about it, but I just waited for a while to see if I noticed a pattern emerging or to better understand him. We laugh about that misunderstanding even four years later.
My point is to just sit it out and see if it's something you can come to understand. A lot of people will stop texts after a while and leave gaps. Personally, I would say "I have to go ________; talk to you when I'm done!" which is why I can understand how not doing so might come off as not caring enough about you. But you will find with this girl that she will show she cares in her own way, and when you've been dating for a while, she may start that habit because you guys wi have a long, ongoing conversation that never really ends.