From what you write, it seems text 1 did not warrant a reply: no direct question but merely a hope that the files would open. Seeing there was no problem opening the file and you did not request anything specific (e.g. need for connection or reassurance) she did not feel the need to reply. As you mention, content of the file is better discussed face-to-face.

Text 2 was you explicitly reaching out to her. Hence, her reply to text 2.

It really doesn't read as T going back on her word. She shows she is there when you need her and responds to you accordingly.

I would however suggest for you to bring it up if it affects you.. It might be a difficult conversation but she would better appreciate where you were/are coming from i.e. need for connection etc.