I like this girl, but its like talking to a brick wall. she cant hold a convo?

Im a junior in high school, i talk to this girl quite a bit and in person shes fine, but when we text its like a few word answers and im the one doing the talking, most of the time its the other way around. my friend who hooked us up, insists thats just how she is and to go through it and eventually ill get her, but its startin to piss me off. how can i get her to talk?