My Most Difficult Texter Yet

Sooooo I've been seeing this girl for a few weeks, the kinda whose a little private, got strong ethics blah blah blah.
She has great interest when were together even though she cancel's alot.
Biggest problem is that I can't build up any text momentum with her, I've never come across anyone so difficult, I feel I need to talk her through text etiquette.
Anyone come across this type of girl.......... strategies, tactics or magic tricks to suggest?