The girl said that she would go out to travel with me alone, but the chat was hot and cold at ordinary times, and sometimes she hinted at me and sent me her photos.

From your description, you have feelings for her, too. Did you tell her directly? There are many reasons why girls are hot and cold. Guess for yourself. It's really painful and tangled. It's better to be straightforward. Whatever the outcome, at least be at ease. In your situation, unless a girl takes you to anger another person, it must be interesting to you.