Perhaps she's simply got the good sense to realise that texting is an appalling way to develop a relationship. It's great for things like confirming dental appointments or making straightforward business arrangement but it's totally pathetic in situations where it's all far too easy to misinterpret what's being said.
Make it a rule to NEVER text her unless, for example, you only require a yes/no answer. (e.g. "Fancy a movie this evening?"). Otherwise ONLY phone her; you'll simply be following her fine example.